Sew a Simple Open Abaya: A Measured Project

A simple open abaya can begin with three rectangles: one long body piece folded across the shoulders and two separate sleeves. This project turns those pieces into an unlined outer layer with a shaped neckline, straight sleeves, a bound front opening and neatly enclosed hems. There are no shoulder seams, sleeve caps, buttons or zip in this design.

The instructions give the cutting calculations, a worked example, a paper neckline and the order of construction. The dimensions and seam relationships have been checked on paper; the garment has not been physically sewn or fitted. Make a full-length toile, meaning a trial garment in inexpensive cloth of similar behaviour, before cutting your chosen fabric.

The finished front hangs open. Choose an under-outfit that provides the coverage you want independently. Adding a fastening would require a different allowance and fitting plan: the two front edges here have no overlap.

Understand the shape before choosing dimensions

The body is straight from its underarm level to the hem. Its width carries across the shoulders, and the sleeve joins sit beyond the shoulder points on a typical loose fit. The sleeves keep the same circumference from the joining seam to the cuff. Expect a relaxed outline with fabric beneath the arms, rather than a shaped shoulder or close wrist.

That simplicity has consequences. Increasing the body width moves each sleeve join outward. Increasing the sleeve circumference also lowers the underarm. The calculations below keep those changes connected, so an alteration to one rectangle does not quietly change the reach of the finished sleeve.

Use this design only where you want a straight, open outer layer. A sharply fitted shoulder, narrow cuff, flared skirt or different front and back lengths would need further drafting. Resolve those requirements before cutting, rather than adding a series of small corrections to a shape that serves a different purpose.

All measurements below are in centimetres. Keep one measurement sheet beside the paper pattern. Write finished dimensions in one column and cutting dimensions in another; the numbers differ because the seams and hems consume part of each rectangle.

Choose four finished measurements

A loose, straight woven garment with the proportions you want is a useful reference. Compare it over the clothing intended beneath the abaya. A stretch garment, fitted jacket or strongly shaped pattern is a poor reference for these rectangles because its apparent room may depend on construction that this project does not contain.

Symbol	Finished measurement	How it is used
B	Flat body width between the two side seamlines, below the sleeves.	The body cutting width is B plus the two side allowances.
L	Length from the shoulder fold to the finished lower edge.	The full body piece contains two lengths and two hem allowances.
C	Circumference of the straight sleeve after its underarm seam is sewn.	This determines both cuff width and the depth of the body opening.
R	Flat reach from the body centreline at shoulder-fold level to the finished cuff.	Subtract half the body width to find the separate sleeve length.

For B, consider the entire garment width around the fullest clothed part of the body. In this straight draft, twice B is the nominal total width with the front edges brought together. The worked example uses B = 70, giving 140 around the garment. That is a construction dimension, not a body-size label or a recommended amount of ease for everyone.

Record the largest relevant clothed circumference, then compare it with the proposed garment width. The difference is the room available around that level. For instance, 140 around a hypothetical clothed measurement of 112 leaves 28 in total. It does not put 28 on each side, and it does not establish whether the shoulders or arms will move comfortably. The toile answers those separate questions.

For L, use the intended finished shoulder-to-hem length. The shoulder fold is the horizontal line across the top of this draft; its centre is above the cut back neckline. Do not begin the measurement at the back neck edge and silently lose the neckline depth. Check the proposed hem with the footwear you expect to wear.

For C, compare a roomy woven sleeve, the clothed upper arm and the hand that must pass through the cuff. This sleeve does not narrow towards the wrist. Choose its circumference deliberately, then try the whole sleeve on the toile; a roomy cuff alone says little about the underarm.

For R, lay a compatible reference garment flat without stretching it and consider the complete top-line span from cuff to cuff. Half a symmetrical span gives R. Measure across the body centre at shoulder level, including the body width before the sleeve begins. A shoulder-to-wrist body measurement leaves that first part out and cannot be substituted directly.

Calculate the three rectangles

This project uses a 1.5 cm allowance at every joining seam. The lower body edge consumes 4 cm: a first turn of 1 cm, followed by a 3 cm turn. Each sleeve cuff consumes 2 cm through two 1 cm turns. These allowances are already included in the cutting formulas.

First calculate the separate sleeve's finished length: S = R − (B ÷ 2). It must be positive and leave a useful sleeve beyond the body join. If the result is zero or negative, the chosen body width and reach do not belong together in this design. Revisit the measurements before trying to cut an improvised sleeve.

Also check that C ÷ 2 is less than L, and that the chosen neckline half-width is less than B ÷ 2, leaving a useful shoulder bridge to confirm on the toile.

Piece	Quantity	Cutting dimensions
Main body	One	Width B + 3; full length 2 × (L + 4).
Sleeve	Two	Width around the arm C + 3; length along the arm S + 3.5.

The body folds across its width halfway along the full length. There is no shoulder seam allowance to add. The sleeve length includes 1.5 for its body join and 2 for its cuff. Its width includes 1.5 at each edge that will meet in the underarm seam.

The neckline and centre-front opening receive binding around their cut edges. They have no extra turning allowance and no 1.5 cm neckline seam allowance. Keep that distinction on the paper: adding a seam allowance everywhere would change the neck opening, while turning the front edges under would narrow the body.

Work through one complete example

Suppose the selected finished dimensions are B = 70, L = 135, C = 50 and R = 80. These illustrate the arithmetic; use the values settled for your own toile.

• The separate finished sleeve length is 80 − 35 = 45.
• Cut the body 73 wide and 278 long. Its shoulder fold is 139 from either short end.
• Cut two sleeves, each 53 around the arm by 48.5 along the arm.
• After the side seams, the body is 70 flat. After the lower hem, its fold-to-hem length is 135.
• Each sewn sleeve is 50 around. Its body join and cuff consume 3.5 of the 48.5 length, leaving 45.
• The finished flat reach is 35 across half the body plus 45 along the sleeve: 80 on each side, or 160 cuff to cuff.

Check those relationships in reverse on your own sheet. Subtract the allowances from the proposed cut pieces and recover all four finished measurements. This catches an added allowance counted twice, a missing cuff turn or a sleeve measured from the wrong starting point before any fabric is involved.

Keep changes to width, length and reach connected

If the example body needs 12 more around it, B increases by 6, from 70 to 76. The body cutting width becomes 79. Keeping R at 80 means the separate finished sleeve becomes 80 − 38 = 42, so its cutting length becomes 45.5. Leaving the old sleeve length unchanged would add 3 to the reach on each side.

If only the finished body length needs 5 more, L becomes 140 and the full body cutting length becomes 288. Both front and back gain 5. The body width, sleeve dimensions and underarm depth remain unchanged. The longer front edges will also need more binding, so measure the revised opening.

If C increases from 50 to 54, the sleeve cutting width becomes 57. The finished underarm sits 27 below the fold instead of 25. Its raw half-depth before seaming becomes 28.5. This change gives more sleeve circumference and lowers the join; it is not simply a wider wrist opening.

Change one variable on the toile at a time and write down every dependent dimension. Do not enlarge the body-side opening while leaving the sleeve joining edge unchanged. The two pieces must still meet without gathering or stretching.

Mark the body and sleeve patterns

Draw the body rectangle on paper, joining sheets securely if necessary. Mark its centreline along the full length and its shoulder fold halfway across the length. Label one half FRONT and the other BACK. Mark the finished hemline 4 above each short raw edge.

Draw a sleeve rectangle with its dimensions written beside the correct edges. Mark the midpoint of the body-joining edge and a line from that midpoint to the cuff midpoint. This becomes the sleeve's top fold. Label the opposite edge CUFF and mark its finished fold 2 inside the raw edge.

Here, “length” means the direction along the arm, even when its number is smaller than the width. In the example, the two 53 cm edges become the body join and cuff; the two 48.5 cm edges meet beneath the arm. Folding the 53 dimension in half gives a raw sleeve depth of 26.5. The underarm allowance reduces the sewn depth to 25. Label the edges by their jobs before folding, rather than assuming the longest edge runs along the arm.

Before making a second paper sleeve, check the first against the formula. You need two identical rectangular sleeve pieces; no left- and right-shaped sleeve caps are hidden in this plan. Keep the paper pieces until the toile and final fabric agree with them.

Draw the shallow back neck and curved front opening

For the example neckline, mark points 9 either side of the body centre on the shoulder fold. The total width there is 18. Mark a back-neck line 3 behind the fold, extending 6 to either side of centre. This gives a straight central section 12 wide.

Round each end of that section up to the shoulder-fold point with a quarter-circle of radius 3. A compass makes the shape reproducible: its centres are on the shoulder fold, 6 either side of the body centre. The arcs meet the straight back section horizontally and the front opening vertically.

For the right front curve, plot the following points. Measure the first column down from the shoulder fold towards the front hem, and the second sideways from the body centreline. Draw one smooth curve through them, then mirror it on the left. The curve begins almost vertically at the shoulder and becomes vertical again as it reaches the centre opening.

Distance down the front	Distance from the centreline
0	9
4.5	7.6
9	4.5
13.5	1.4
18	0

Continue straight down the centre front from the final point to the front hem. Join the curves smoothly, without making a polygon from the plotted points. Draw the whole shape on separate paper first, fold it along the centreline to check symmetry, and use that template on the body.

This neckline is a starting shape for the example, not a size chart. The front opens fully, so dressing does not depend on passing the head through a closed neck hole. Its width, depth and position still need to suit the wearer. Preserve any successful toile changes as a new paper template before cutting the final cloth.

Make a controlled change to the paper neckline

If the toile indicates that you should try an opening 20 cm wide at the shoulder fold, retain the back depth of 3 cm by making its straight part 14 wide. The two quarter-circle centres move to 7 either side of centre, and the shoulder points move to 10. The circles still have radius 3; the extra width goes into the central straight section.

For that wider front, multiply the table's sideways distances by 10 ÷ 9, keeping its downward distances unchanged. The revised sideways positions are approximately 10, 8.4, 5, 1.6 and 0. Redraw a smooth curve and test it on the toile before accepting the change. The body and sleeves remain the same, but the bridge of fabric between the neck and each sleeve join becomes 1 cm narrower.

Change the front drop separately if needed. For a trial drop of 20, place the five front points at downward distances of 0, 5, 10, 15 and 20, using the accepted sideways measurements. Record the new shape as one complete template. Cutting a little more away repeatedly provides no dependable pattern to return to.

Plan the layout on usable fabric width

Choose a stable, non-stretch woven fabric with no nap or one-way design. Folding the body over the shoulders reverses the lengthwise direction from front to back. A directional print would therefore face opposite ways on the two halves. This particular layout is designed to avoid that complication.

Keep the long body axis and each sleeve's length axis parallel to the selvedge. Work from the prepared cloth's usable width, excluding firm selvedges and any defects, rather than the advertised bolt width. Leave a little space between the pieces so each outline can be cut accurately.

For the example, a usable width of at least 128 cm accommodates the body width of 73, a 2 cm gap and a sleeve strip 53 wide. Place both sleeves, each 48.5 cm long, consecutively in that strip. Their combined length of 97, plus a gap between them, fits beside the body length of 278. Keep their sleeve-length direction running with the body length.

With narrower cloth that still accommodates the 73-wide body, place the two sleeves after the body instead. The bare piece lengths then total 278 + 48.5 + 48.5 = 375. Squaring, cutting spaces, flaws and preparation losses are additional. These are cutting envelopes, not guaranteed purchase quantities.

If the usable cloth is narrower than either required piece, stop and redraw the layout before buying or cutting. Rotating a sleeve sideways changes its grain direction. Adding a centre-back seam changes the body pattern. Neither is a space-saving adjustment already covered by these dimensions.

Lay the complete paper pieces within a marked rectangle representing the available cloth. Account for binding separately. Keep useful offcuts for seam samples, but do not count a narrow leftover strip as sufficient until the actual test piece fits within it.

Prepare the cloth and the machine

Follow the fabric's care information when preparing it, and prepare compatible binding before final measuring. Mark the chosen right side consistently. Press out handling creases without stretching the cloth, then recheck the usable dimensions. The Sewing & Craft Alliance's Preparing to Sew, Guideline 4.104, March 2006 explains preparation, right-side identification and grain direction. Its principle here is straightforward: establish the cloth's usable state before making the final cuts.

If you are comparing materials, our fabric tests for making a jilbab cover preparation and representative seams in long garments. Retain this project's stable-woven requirement when choosing among samples.

Gather paper, a ruler, tape measure, compass, tested marking tool, shears, pins or clips, hand-sewing needle, sewing machine and pressing equipment. Choose thread and a needle system compatible with the machine and cloth. For poplin, SCHMETZ lists Microtex or Universal needles in 60/8–80/12; that range is a starting point for a sample, not a fixed setting. Check the actual layers at a seam, cuff and bound hem corner. SCHMETZ, Needles by Fabric Type, accessed October 2026.

Use the full construction for the toile

Make the trial garment at full length using the rectangles, neckline and construction sequence below. A short sample top cannot show how this long body hangs or where its lower edge falls. Use inexpensive cloth with reasonably similar stability and weight, and include both sleeves.

Write the centreline, shoulder fold, intended hemline and underarm levels on the trial pieces. Those references let you distinguish a sewing error from an unsuitable measurement. Keep seam allowances available for inspection. Include a representative bound neckline and a lower front hem corner, because the final edge treatment can change how those areas sit.

Try the toile over the intended outfit. Let it hang naturally before assessing it. Look at the front, back and sides; do not hold the front edges in a position they abandon as soon as your hands drop.

• Reach forward and bend the elbows. Check whether the cuffs still sit where wanted and whether the underarm pulls the entire body upwards.
• Sit and stand. Check the room across the upper back, chest, hips and thighs, including the underlayer.
• Put each hand through the cuff. Look at how much of the underlayer's sleeve becomes visible when the arm moves.
• Walk and use an ordinary step. Check the front corners and back hem for clearance without lifting the garment by hand.
• Check the neck while looking forward and turning the head. Watch for a back edge that presses into the neck or an opening that slides off the shoulders.

Record the cause before changing a number. A short sleeve is different from a body that rides upwards when reaching. More body width also changes the sleeve join position; more sleeve circumference lowers the underarm. If the straight shape cannot give the balance or movement you need, choose a more suitable pattern or work with a sewing teacher.

When the toile is satisfactory, transfer its final dimensions and neckline to the paper. Measure the amended pieces again. Keep the accepted toile as the reference beside the machine, rather than relying on a list of changes that has never been combined into one garment.

Cut and label the final pieces

Lay the prepared fabric out without any length hanging unsupported from the table. Position the body and two sleeves according to the accepted layout. Compare each rectangle with the cutting sheet, then transfer the fold lines, front/back labels, hem lines and sleeve placement marks.

Open the main body fully into a single layer before cutting the neckline. Position the paper neck template on its centreline and shoulder fold, with the deeper curve pointing towards the labelled front. Cut the neck shape and continue along the centre front to that half's raw hem. Keep the back centre intact.

Cutting through both shoulder-folded layers would make the deep front opening in the back as well. Check the FRONT label and feel beneath the scissors before beginning that cut. Once the front is open, label its two halves so they remain easy to recognise when the garment is folded right sides together.

Check the cut sleeves against one another, including the body-joining edge and cuff direction. Place each against its paper pattern and compare both dimensions. Recheck the body centreline and fold before assembly: an inaccurate fold would assign different lengths to the front and back even if the outer rectangle were correct.

Stabilise the neckline and finish raw seam edges

Staystitch the cut neckline promptly through one layer, about 5 mm from the edge so the line will be covered by the binding. Sew each back half from shoulder to centre back, and each front curve from its lower point towards the shoulder. Keep the cloth supported and compare it with the template afterwards. This adapts the directional method in the Sewing & Craft Alliance's Staystitching, Guideline 11.135, January 2007; it preserves the intended opening rather than joining two pieces.

Test a zigzag finish close to the raw edge on spare cloth. Finish the body side edges and each sleeve's joining and underarm edges separately, retaining the full 1.5 cm allowance. The neckline and front will be bound; the cuff and lower raw edges will be enclosed by their hems. Avoid trimming away width needed by the calculations. The Sewing & Craft Alliance's Seam Finishes, Guideline 11.115, September 2005 describes zigzag finishing and the need to match a finish to the fabric. Keep a sample that lies flat without a hard ridge.

Join the sleeves and close the body

1. Along each body edge, mark raw sleeve corners (C + 3) ÷ 2 above and below the fold. Mark sewing endpoints C ÷ 2 from the fold, 1.5 inside the edge. Sleeve endpoints are 1.5 from both joining and adjacent underarm edges.
2. Lay the body opened flat, right side up, and sleeve right side down over it. Match raw joining edges, midpoint to fold and raw corners to marks. Pin through paired endpoints. Sew at 1.5 only between endpoints; secure. Open and press allowances towards the sleeve.
3. Fold at shoulders and sleeve midlines, right sides together. Pin-match endpoints. Sew each body side from hem to endpoint at 1.5, keeping sleeve allowances clear; secure ends.
4. Sew each sleeve underarm separately from cuff to endpoint at 1.5, keeping other allowances clear. Stitch only two layers and secure ends.
5. Turn right side out and inspect both junctions. Unpick and correct any hole, twist or trapped allowance. Do not clip the junction.

Aim for Quality, Flat set sleeves and a square armhole, 9 July 2024.

Check length and sew the hems

Check the assembled garment's length. Turn the lower edge 1 cm to the wrong side, then 3 cm from the new fold: total take-up 4 cm, finished hem depth 3 cm. Make two successive 1 cm turns at each cuff. Press and baste with adjoining seams aligned.

Stitch near the inner fold, keeping the remaining garment clear. Inspect the reverse. Complete the body hem before binding, establishing the lower corners where the tape ends. Sewing & Craft Alliance, Simple Hems, Guideline 11.130, July 2006.

Measure the finished opening for binding

Use soft woven double-fold bias tape about 1 cm wide when folded, with care requirements compatible with the garment. Check its actual folds and thickness on a sample. Ordinary straight ribbon does not replace the specified bias tape at these curves.

Measure from one finished front hem, up that front edge, around the back neck and down to the other finished front hem. A non-stretch thread laid along the edge can be straightened against a ruler. Add 1 cm for turning in each tape end and a working margin; 20 cm is the margin used in this project plan.

The unaltered example's opening is approximately 296 cm before those additions. The exact length changes with the drawn curve, fit adjustments and hem. Measuring to the raw body edges before turning the hems would add 8 cm that will later disappear. Use the actual finished opening rather than ordering from the approximate figure.

Use one continuous prepared length for this example. Do not stretch a short piece to make it reach.

Shape the binding before attaching it

Use the neckline template to check a sample of the binding around the back corners and front curve. Shape it gently with the permitted pressing method, then let it settle. The Sewing & Craft Alliance's Using Bias Tape, Guideline 6.186, August 2011 explains pre-shaping around curves.

The strip must follow the opening without pulling it smaller or making a ruffled edge. If the sample refuses the curve, revisit the tape's width, weight and handling before sewing the garment. Keep the cloth's cut edge at its intended length. Also test the lower corner, where the binding crosses the already folded body hem.

Bind the front and neckline continuously

Turn each short tape end 1 cm inward so it finishes flush with the corresponding hem. Open the narrower long fold. Place the tape right sides together with the garment, raw edges aligned, and sew in the first crease. Refold around the edge; its wider underside should cover the first stitching. Baste, then stitch from the right side close to the binding's inner edge, catching the underside throughout.

Keep the opposite front clear and inspect the reverse as you sew. Leave the already shaped neckline untrimmed. Coats & Clark, Sewing From A to Z: Bias Bindings, hosted by the Sewing & Craft Alliance.

Inspect the complete garment

Look inside every seam and along the reverse of the binding. Check for skipped areas, exposed raw edges, loose ends and an underside fold missed by the topstitching. Check that the hems remain even, the front corners finish neatly and neither sleeve has twisted during assembly.

Try the garment once more over its intended outfit and repeat the movements used for the toile. The New Mexico State University guide Clothing Construction Standards, C-214, revised February 2015 treats smooth seams, secure stitching, suitable ease and an even hem as parts of construction quality. A neat surface alone is insufficient if a join opens or the cut restricts movement.

Trace a problem back to the relevant measurement

What you notice	Check before altering
The sleeves finish farther out than planned.	Recalculate R from half the actual finished body width plus the finished sleeve length. Check whether body width was increased without shortening the sleeves.
The sleeves are roomy but the underarms sit unexpectedly low.	Compare the actual sleeve circumference with C. Its half determines the underarm level; extra circumference also changes depth.
One cuff is shorter.	Compare both raw sleeve lengths, joining allowances and hem take-up. Find the unequal stage before trimming either finished sleeve.
The back opening resembles the deep front curve.	Check the cutting record. The body may have been cut through two folded layers; pressing cannot restore the removed back fabric.
The front edges are unequal at the bottom.	Compare the shoulder-fold position, two body lengths and hem turns. Then check the garment's balance on the wearer.

Keep any correction tied to a recorded cause. If the sewing matches the paper but the garment still behaves poorly, the paper needs reconsidering. Repeatedly trimming the cloth makes it harder to recover a clear reference for the next attempt.

Keep the pattern useful for the next make

Store the final paper pieces with the accepted values of B, L, C and R, the actual cutting dimensions, neckline template, fabric details and successful seam samples. Record the binding length measured after hemming. Date the version so an earlier sleeve or neckline does not get mixed into the next garment.

Once the plain abaya hangs and moves as intended, consider additions separately. If storage is useful, our measured patch-pocket project for an open abaya covers fabric support, placement and attachment. Establish the complete garment first, then judge whether an extra component improves the way you use it.