If you want your hand-sewn garments to fit well — and really, how could you not? — you need to be using a muslin.
Sewing a muslin is a great way to test out the construction and fit of a pattern without the risk of wasting good fabric on a piece of clothing you ultimately aren’t pleased with. Learning how to fit a muslin is the first step towards total sewing satisfaction.
Let's review the process: You typically make a muslin by cutting the pattern pieces from inexpensive, easy-to-find fabric. That way, you won’t mind tossing the muslin when you’re done with it.
In most cases, you’ll want to transfer all pattern markings to the muslin using a dressmaker’s wheel and carbon paper. This helps you see where and how to make adjustments to the final garment. If you know that you might need to let out a pattern in a particular spot, such as around the hips or bust, you can leave extra fabric in these areas.
After you cut out the pattern pieces, ] sew the muslin using a long, basting stitch. You don’t need to worry about any pattern pieces that don’t show on the right side of the garment, such as neck and armhole facings. Seams don’t need to be finished, and most of the time you can skip adding any closures (such as a zipper) and hems.
Once you’ve finished your muslin, you're going to use it to work on the pattern's fit. It's a three-part process.
How to Fit a Muslin
1. Try the Muslin On, Right Side Out
If you have a dress form filled out to your measurements, you’ll probably find it easier to fit your muslin on that. Lacking that, you'll need to try the muslin on yourself . For some patterns (like a dress with a back zip), phone a friend to help. If no one’s available to pin you into the garment, it’s in your best interest to add any closures to get the best idea of how the garment actually fits. Be sure to baste them in and you’ll be able to easily rip them out and reuse for your final garment.
If you’re satisfied with the garment fit, congratulations! You can skip to step 3. More likely, though, you’ll need to make some fixes.
2. Try the Muslin On, Wrong Side Out
This is when you’ll pin and mark any adjustments for the final garment (or the next muslin, if you’re having major fit issues!). Perhaps the side seams need to be taken in, or maybe you need to lengthen the bodice so the waist is in the correct spot. Maybe the bust darts need to be let out or taken in. Adjust as needed until you're satisfied with the fit.
3. Take the Muslin Off and Deconstruct It
At this point, you can either transfer any changes directly to your pattern (if they are small changes) or make new pattern pieces based on the muslin (if the changes are more complex).
Now, with the help of your muslin you're well on your way to making a garment you'll totally love!