If you're like me, you sew your own clothes because you want a custom fit. That usually means you adjust the pattern before taking scissors to fabric.
But if you're not also fitting while you sew, you're missing out on an opportunity to make your garment fit as well as it could.
Fitting as you sew means either using a dress form that's a good replica of your body shape or trying on the garment. On a lot of dress forms you can adjust the circumference at various points, but it's harder to get the vertical measurements right. That's when trying on the garment really pays off.
Are you really committed to a custom fit? Let me tell you what I know.
Before you cut out your fabric, consider changing all seam allowances to 1 inch instead of whatever the pattern calls for. That way, you'll have a little extra fabric to work with in case you need it.
In a typical pattern with ⅝-inch seam allowances, adding another ⅜ inch on the side seam will give you another 1½ inches total of extra room at the bust, waist and hip. You might be surprised at how the fit of the garment can change by letting it out just a little bit where you might need it.
Don’t forget to add the same seam allowance to any sleeve seam — remember, your sleeve will need to be larger at the underarm seam as well. You can taper that extra seam allowance away as you sew the seam.
Most sewing patterns are designed for a person who is five-five or five-six. If you're shorter or taller, the vertical measurements might not match your body shape. And what if you have a short torso and long legs, or vice versa? Bottom line: The bust curve or shoulder height in a pattern may need adjusting.
Sometimes the dress or top is too big, or the bust point lands below the apex. If that's your issue, you can take the garment up at the shoulders. You'll have to adjust any facings or collar too.
Say your neckline is just too low or just doesn't fit right. If you added extra to the seam allowance, you can raise the neckline slightly. On the flip side, don't be afraid to take away at the front neckline if your garment is too high or restrictive. You can fix that by making the curve deeper in the center front.
Princess seams give you a lot of leeway in fitting the bodice, whether you need to take it in or let it out. Even if you don't add to the seam allowance, sewing each front princess seam with a ⅜-inch seam allowance over the bustline instead of a ⅝ inch gains you 1 inch (4 times ¼ inch) over the front bodice.
Shoulder princess seams are another perfect opportunity to fit as you sew. Choosing a pattern size based on bust measurement might get you a pattern that fits in the body but not in the neckline or shoulders. Taper some width away front and back at the shoulder using the shoulder princess seam line and you won't need to make any change to the sleeve insertion.
Center Back Fit
To get a good fit across the center back — which means the whole neckline — it pays to check the placement of the zipper in a center back seam. You don't have to follow the pattern's seam allowance for a zipper application.
In the image above, you can see I took out about 1½ inches on either side of the top of the zipper, tapering away to the regular seam allowance at the waist. This made the bodice back fit well.
If you find you have gaping at the center back on finished garments, leave the zipper application until the last step and baste it in. Try on the garment and see if making some adjustment in that center back seam solves the problem.
There's one fit adjustment I always make as I sew: placement of the waist seam. Depending on your body shape and height, you may have to raise or lower the waist seam. (That's another reason to put in the zipper after putting together the the garment.)
Sometimes you have to raise in the back and lower in the front, or the reverse. Either way, you want to create a waist seam that's horizontal and equidistant from the floor on both the front and back of the garment as viewed from the side.
Breaking the Rules
One more important thing about fitting on the fly: You don't have to follow the pattern!
For example, instead of sewing a dress's bodice and the skirt separately and then attaching the two together, sew the entire front, the entire back, and then start with the shoulder seams and work your way down the body, pin basting and adjusting fit.
This process may take a few more trips back and forth to the sewing machine. But it's worth it for a perfect fit!