Muslin / Toile

A muslin (the usual American term) or toile (the British and French term) is a test version of a garment, sewn from inexpensive fabric before cutting into the real fashion fabric. It shows how a pattern fits and behaves on an actual body in a way a flat piece of paper can't. The name comes from the fabric traditionally used for it: plain, unbleached cotton called muslin in the US and calico in the UK. Confusingly, in the UK "muslin" means a much finer, open-weave cotton.

In couture and professional patternmaking, the toile is a formal stage in the design process. The design is perfected in toile before any expensive fabric is touched. For home sewists it's the single most effective fitting habit there is.

What to make it from

The test fabric should behave like the real fabric, or the test will mislead you:

• For crisp woven garments, calico/muslin, old bedsheets or inexpensive poplin work well.
• For drapey garments, such as rayon dresses or silk blouses, use a cheap fabric that drapes similarly, for example an inexpensive rayon or polyester crepe. Stiff calico makes a soft design look boxy and hides drag lines.
• For knits, test in a knit with the same stretch percentage. A knit garment tested in woven fabric tells you nothing.
• For heavy coats, use something with similar thickness, or the muslin will fit more closely than the finished coat.

Preparing a muslin

1. Cut with wider seam allowances at side seams and centre back, about 1" (2.5 cm), so seams can be let out as well as taken in.
2. Transfer markings to the right side with a marker: centre front, centre back, the grainline, bust point, waist line and hip line. On a muslin that fits, horizontal lines stay level and vertical lines hang straight. When they tilt or curve, they show you where and how the fit is off.
3. Leave out details that don't affect fit: facings, pockets, linings, and usually one sleeve. Only one half of a symmetrical garment is needed for fitting, although a full muslin is easier to judge.
4. Sew with a long stitch so it's quick to unpick, and close the opening with pins or a zip.

Fitting it

Try it on over the underwear you'll wear with the finished garment. Work from the top down, neck and shoulders first, then bust, waist and hips, because everything below hangs from the shoulders. Pin out excess, slash and spread where it's tight, and mark every change directly on the muslin with a pen. Then take it apart, press it flat, and use it to correct the paper pattern. The Fitting and Alterations page explains how to read the wrinkles and which adjustment fixes which problem.

Expect to make more than one. A second muslin confirms that the first round of changes worked and didn't cause new problems elsewhere.

Wearable muslins

A wearable muslin is a test version sewn in an inexpensive fabric you'd actually wear, finished properly. If the fit is right, you get a garment and a fitted pattern at the same time. It's a good approach for simple garments, or for patterns that need only small adjustments.

When you can skip it

• Patterns you've already made and fitted.
• Loose, unfitted shapes such as boxy tops, gathered skirts and wrap garments, where small fit errors don't show.
• Garments whose seams you can baste together in the real fabric and fit as you go, as long as the fabric won't show holes from unpicking.

Anything fitted, anything made from expensive or irreplaceable fabric, and anything from a new pattern company whose sizing you don't know is worth a muslin. A few metres of calico is far cheaper than recutting a silk dress.