Sew a Square Bandana Underscarf: Size, Hem and Fit

A square bandana can be folded into a triangular underlayer, tied behind the head and worn beneath a larger hijab. Making the square yourself lets you choose its finished size, fabric and edge finish instead of trying to make a small ready-made accessory stretch around a hairstyle it does not suit.

The sewing is straightforward: cut a square and finish its four edges. The more thoughtful part is choosing a size that ties comfortably and checking how the resulting triangle behaves under your own scarf. The project below uses a 65 cm finished square as a worked example. Choose your size through a cloth trial first; 65 cm is a calculation example, not a universal head measurement.

This is a flat, tied underscarf. It has no fitted crown, elastic opening or enclosed hair pocket. The outer hijab or khimar still needs to provide the coverage you want, and the bandana should remain comfortable when that layer is added.

Try the shape with a square you already own

Use a soft square scarf or a piece of suitable cloth to explore the shape before buying or cutting fabric. Fold one corner to the diagonally opposite corner, bringing the edges together. The result is a double-layer triangle with one long folded edge, two side tips and a point at the back.

Place the middle of the folded edge where you want the underscarf's front to sit. Let the point fall backwards over your usual hair arrangement. Bring the two side tips towards the nape without dragging the front edge backwards. Check whether there is enough loose fabric to tie a knot while keeping the front and sides comfortable.

The cloth needs spare length for the tie, not merely enough length for the tips to meet. Hold the tips in the intended position before knotting them. If you have to pull the cloth firmly against your head just to cross them, use a larger square. If the tips overlap generously but the knot is bulky, investigate the fabric thickness before deciding that the whole square is too large.

Check the back point separately. It should lie in a manageable position rather than bunching into a wad under the outer scarf. A larger square gives both longer tying ends and a deeper triangle. You cannot increase one without increasing the other in this simple square design.

If your trial cloth is larger than needed, fold its edges under temporarily to explore a smaller square. Extra folded edges add bulk, so use that trial to judge approximate dimensions and placement, then make the small hem sample described below to judge the real edge finish.

Understand the square before calculating the cut size

The measurement across one side of the square is not the length of the edge that goes around the head. Folding from corner to corner makes the diagonal the long edge of the triangle. A 65 cm square has a diagonal of approximately 91.9 cm; the perpendicular distance from the middle of that long edge to the back point is approximately 46 cm.

Those are flat geometric measurements. They do not say how much of the cloth will remain for the knot after it passes over your head and hair. Your chosen front position, hair volume, fold and knot all affect the fit.

Finished square side	Long diagonal when folded	Triangle depth from midpoint to back point
55 cm	About 77.8 cm	About 38.9 cm
60 cm	About 84.9 cm	About 42.4 cm
65 cm	About 91.9 cm	About 46.0 cm

Use the table to understand what changes when you choose a larger square. It is not a size chart based on age, head circumference or hair type. If you already have a comfortable square, measure it flat and use that finished dimension as a more useful starting point.

Record the successful trial in a few specific notes: square size, fabric thickness, front-edge position, location of the knot and which outer scarf you wore over it. This avoids repeating a size that worked with one hair arrangement but became awkward with a different combination.

A worked choice between two sizes

Suppose a 60 cm trial square sits comfortably across the front, but its tips leave too little fabric for an easy knot. Testing a 65 cm square adds approximately 7.1 cm to the long diagonal, not merely 5 cm. It also adds about 3.5 cm to the triangle's depth. Try both changes together: the longer tips may help, while the deeper back point may need more space beneath the outer scarf.

If the larger square ties well but bunches at the back, first let the point lie flatter and check the hair arrangement. If the smaller square has enough length but still feels tight, the answer may be a gentler tie or a softer material rather than another size increase. Keep the front position comparable while testing, otherwise a change in placement can be mistaken for a change in size.

Once you prefer one trial, measure its finished side and add the hem allowance to that dimension. For a successful 63 cm square, for example, the same edge finish requires a 65 cm cut square. You do not need to choose one of the round-number examples in the table. Avoid cutting the back point off the folded square as a quick fit correction: that creates new raw edges and changes the pattern into a different shape that needs its own finishing plan.

Select fabric for two layers, a knot and skin contact

Fold a fabric sample diagonally and feel the doubled cloth, not only the single layer. Then tie two corners loosely together. A material that feels pleasant when flat can make a firm knot or thick edges once folded.

A soft, lightweight, stable woven fabric is a manageable starting point for this sewing method. A fine cotton lawn or a similar soft woven cloth may be suitable if its actual handle and care requirements work for you. Avoid choosing by fibre name alone: two cotton fabrics can differ considerably in stiffness, thickness and surface feel.

Stretch jersey requires different handling and may not behave like the woven square used here. Very slippery satin, loose weaves and delicate chiffon also make narrow hems harder to control. Practise with a stable scrap before attempting a precious or difficult fabric.

Look at both faces of a print. The back may become visible at the tips or where the triangle turns. A one-sided print is still usable, but fold the sample as you intend to wear it before cutting. A large motif that looks attractive on the flat cloth may disappear under the outer hijab or land awkwardly at the front edge.

Keep this underlayer plain in construction. Beads, thick embroidery, hard labels and raised trims can create pressure beneath another scarf or interfere with the tie. Colour can provide any visible detail you want without adding hardware. If you prefer the underlayer hidden, check its colour beneath the actual outer scarf in ordinary light.

Prepare the cloth and make a corner sample

Obtain the fabric's care instructions before sewing. Prepare washable cloth using the washing and drying method appropriate to that material and your intended future care, then let it dry and smooth it according to its pressing instructions. Measure and cut afterwards. Do not assume all fabrics can be tumble-dried or pressed at the same temperature.

The Sewing & Craft Alliance's fabric-preparation guidance (4.104) explains the value of preparing fabric before cutting and checking the direction of its woven threads. For this square, keep two edges along the lengthwise direction and the other two across it. A printed stripe is not always aligned with the weave, so check the cloth rather than using the print as your only ruler.

Cut a 12 cm square from an offcut. On two opposite sides, turn 5 mm to the wrong side, then another 5 mm, and stitch the folds. Repeat on the remaining two sides. The sample should finish at approximately 10 cm square.

Inspect its corners carefully. The second pair of hems folds over the first pair, producing thicker areas. Feel those areas between your fingers and against the location where the bandana tips will sit. If the corners are stiff or scratchy, use a lighter fabric or another appropriate edge finish before making the full square.

This small sample also lets you choose thread, needle and machine settings. Use a straight stitch that secures the fold without puckering it, and a needle suited to the material. Check the reverse for skipped stitches, loops or raw fibres escaping from the folded edge. Adjust the sample rather than experimenting on the full bandana.

Calculate the fabric you will cut

Each edge in this project is folded 5 mm and then 5 mm again. Together those turns consume 1 cm at each side. With two opposite edges, the total reduction is 2 cm across that dimension.

For a finished 65 cm square, cut a 67 cm square. After hemming all four edges, the visible flat area measures approximately 65 cm in both directions. The finished hem itself is about 5 mm wide; it is not a 1 cm wide strip despite using 1 cm of fabric.

Desired finished square	Fabric to cut	Edge treatment
55 × 55 cm	57 × 57 cm	Two 5 mm turns on every side
60 × 60 cm	62 × 62 cm	Two 5 mm turns on every side
65 × 65 cm	67 × 67 cm	Two 5 mm turns on every side

Measure the usable cloth after preparation, excluding a stiff selvedge or damaged area you do not want in the finished bandana. For the largest example, you need at least 67 cm of usable width and 67 cm of usable length for the square itself, plus offcuts for testing. Buying exactly that amount before washing leaves no room for shrinkage or squaring a crooked cut.

If you plan two squares across the width, two 67 cm pieces require at least 134 cm of usable width. A fabric labelled 140 cm wide might allow that layout, but only if its actual prepared width, edges and print placement leave enough room. Lay out both squares before assuming the nominal width guarantees two.

Mark and cut an accurate square

Lay the prepared cloth flat without pulling it. Establish one straight edge following the weave, then mark a right angle for the adjacent edge. Measure 67 cm along each side for the example and join the marks using a long ruler or a carefully aligned paper square.

Check all four side lengths before cutting. Check that opposite edges run parallel and the corners form right angles. If you fold the marked square diagonally, the two adjacent sides should meet rather than leaving one edge consistently longer.

Do not trim away a mismatch while holding the cloth in the air. Lay it flat again and find the cause: a crooked measurement, stretched cloth or a fold that is not actually corner to corner. Correct the markings before taking the scissors to it.

Cut smoothly along the lines and keep the offcuts for testing. Mark the wrong side discreetly if both faces look similar. All four hems will turn to that same side, so deciding now prevents one edge being folded in the opposite direction.

Sew the first two opposite hems

Place the square wrong side up. On the first edge, turn the raw edge under by 5 mm. Press only as the fabric allows. Turn it another 5 mm so the raw edge is enclosed inside the fold. Measure along the length; a hem that gradually widens will change the finished shape.

Hold the fold with suitable clips or pins kept away from the needle's path. Sew close to the inner folded edge, through the hem and the main cloth, using the settings that worked on your sample. Remove pins before reaching them and guide the cloth without pulling it forwards or sideways.

Secure the stitching at the ends in a way that suits the fabric. A few reverse stitches may work on your sample; if they create a lump, leave thread tails, bring them to the same side and tie them securely instead. Keep the finish small, because the next pair of hems will fold over these ends.

Repeat on the opposite edge. At this stage, the example should measure approximately 65 cm between the two finished edges and 67 cm between the two remaining raw edges. Checking now is easier than discovering an uneven allowance after all four sides are complete.

Mary Earle-Sigler's bandana tutorial at The Daily Sew demonstrates a narrow, twice-folded hem as a practical finish for a square scarf. Keeping the fold small helps avoid an unnecessarily heavy edge. The 5 mm turns here are the dimensions used for this particular project, rather than a requirement for every bandana fabric.

Finish the remaining pair and control the corners

Turn the third edge 5 mm and then another 5 mm towards the wrong side. Its ends now fold over the two hems you have already sewn. Check that those corners lie flat and that the first hems' raw ends are enclosed.

Sew along the inner fold as before. Approach the thicker ends slowly. If the machine struggles to feed the corner, stop and check the sample settings and foot position; do not pull the bandana to force it through. Follow your machine's guidance for handling changes in thickness.

Repeat on the fourth edge, then remove any temporary pins, clips or basting. Check the entire perimeter from both sides. Pay attention to the last few millimetres at each corner, where a folded edge can escape the line of stitching.

A missed section can be resewn while the square is still flat. An excessively bulky corner needs a different solution: unpick and reassess the fold or practise an alternative finish on a scrap. Do not blindly snip across the finished corner, because that can cut the stitching and expose new raw edges.

Smooth or lightly press the hems as the fabric permits. The finished square should measure close to 65 cm along both directions. Small handling differences are possible, but a noticeably tapered or twisted piece deserves correction before you judge its fit on your head.

Fold and fit the finished underscarf

Fold the square diagonally with the face you want outward, bringing opposite corners together. Smooth the two layers without stretching the long folded edge. Keep the remaining corners aligned so one side tip is not artificially longer than the other.

Arrange your hair in the way you intend to wear it, using your usual comfortable method. Position the midpoint of the folded edge at the front. Guide the side tips backwards while allowing the cloth over the crown to settle; do not pull the tips sharply downwards to flatten every small fold.

Check the ears and temples before tying. The edge should not fold an ear into an uncomfortable position or press where glasses will sit. Bring the ends together at a comfortable place near the nape, make a first crossing, then pause to check the front. Finish the tie only when the position feels right.

Manage the back point separately from the knot. You may let it lie flat beneath the outer scarf or tuck it gently if the fabric and space allow. Avoid cramming the whole point into a tight knot. If the back remains bulky, return to the size and fabric choice rather than simply tying harder.

This simple square has no enclosed pocket to contain all hair. Check the sides and lower edge after tying. If you need a cap with a shaped back or another type of containment, choose that construction instead of expecting the triangle to become a fitted cap through tension alone.

Add the outer scarf and check the complete combination

Put on the actual hijab or khimar you plan to wear. Arrange its coverage independently, then see what the bandana contributes. It may provide a helpful base, but neither a particular fibre nor a knot guarantees that every outer scarf will stay still.

Turn your head, look down and sit against a chair. Put on glasses and any usual hood or coat. Notice whether the knot presses against a collar, whether the front edge moves or whether the two scarf layers slide in different directions.

Check the neck, sides and back as well as the face frame. A neatly tied bandana can still leave areas uncovered that you expect the outer scarf to cover. The finished outfit, rather than the name of the underlayer, tells you whether you have the result you intended.

Then remove the outer scarf once and replace it. If that movement drags the bandana far backwards, practise lifting the outer layer clear and reassess the combination. You should be able to handle the two pieces without repeatedly tightening the inner knot.

The guide to wearing a scarf with an undercap explores the wider interaction between the base, outer fabric and comfort. Use this sewing project to create the square; use the wearing trial to decide whether that square is a useful underlayer for you.

Diagnose the problem before changing the pattern

What you notice	What to inspect first	A useful adjustment
Side tips barely meet	Actual diagonal, front placement and hair arrangement	Try a larger cloth square before cutting another.
Enough length, but a hard knot	Fabric thickness and corner hems	Test a lighter cloth or less bulky suitable edge finish.
Back point forms a lump	Triangle depth and where the point is tucked	Let it lie flatter or reconsider the square size.
Bandana feels comfortable until the outer scarf is added	Extra pressure, stacked folds and knot location	Change the outer arrangement and repeat the complete test.
One tying end seems longer	Square accuracy and diagonal fold	Refold flat before changing the sewn dimensions.

Change one factor at a time. A larger square may solve short ties while making the back point too deep. A thicker cloth may feel easier to handle but create a firmer knot. Recording what changed lets you compare the actual effects instead of replacing everything at once.

There is no need to keep wearing an uncomfortable result to prove the sewing project worked. A neatly made square can be useful as another scarf accessory even if it does not suit you as an underlayer. If the fit is close, however, a small change in placement may be enough; make that trial before cutting away fabric.

Care for the finished square and save the useful measurements

Untie the bandana after wearing it rather than storing it in a tight knot. Follow the fabric's care instructions, allow it to dry fully and check the narrow hems before folding it away. Loose stitching at a corner is easier to repair before the raw edge begins to escape.

Recheck its dimensions and fit after the first wash. Preparing the fabric reduces one source of surprise, but the completed square and its stitching still need observation. If the cloth has changed, record the new measurements instead of continuing to describe it by the original cutting size.

Keep the successful hem sample with a note of the finished square size, cut size and machine settings. If you make another bandana from a different fabric, repeat the sample and wearing trial; the same square on paper can produce a different knot and feel.

A useful homemade underscarf is one you can tie without strain, wear beneath your chosen outer layer and care for without losing its shape. Accurate cutting and a light, tidy hem give you a sound starting point. The final choice belongs to the way the finished bandana behaves on you.