Tips for Achieving an Ideal Fit

The sizes available on the printed pattern should accommodate most body builds, but some customizing may be needed in order to achieve an ideal fit. 

Perhaps most likely to need adjustment is the collar, as it may be slightly too tight or too loose for comfort around the wearer's neck. It should be snug-ish but not uncomfortably tight. 

Our pattern's collars are graded in increments of 1", starting with 14 ½" for the size small.

The collar and collar facing pieces themselves are rectangles, and to adjust the size of the collar, one needs only to adjust the width of the rectangles (the long way). 

Remember that by whatever increment you adjust the size, the end result will be double (since the pieces are placed on the fold)! In other words, if you widen the pattern piece by ¼", the result will be a collar that is ½" looser.

Should you require LOOSENING of the collar, we recommend widening the pattern pieces as described above by whatever increment is necessary for an ideal fit (and this may take a few tries to get just right). Then simply ease in the longer collar while sewing it; you may also stretch the body's neckline if necessary to accommodate the longer collar. 

Should you require TIGHTENING of the collar, we recommend first tapering the collar at the center back - that is, instead of leaving a straight vertical edge on each side of the center back, cutting it at a slight angle, widening from the bottom to top of the collar. This will help the collar better conform to and hug the wearer's neck.

Another option is to take advantage of the 1" seam allowance in the back by taking it in or letting it out as needed (within reason).

A good method for determining exactly where to place the seam line for ideal comfort is to baste or sew the entire undershirt together except for the center back, then stretch it to comfort and pin the back halves together along the center back, using the pin placements for reference. 

If you've chosen to construct the undershirt with sleeves, then you may wish to lengthen or shorten them.

If your sleeves need lengthening or shortening, first determine if the sleeve cuff is comfortable and/or has the desired amount of tautness around your wrists. 

If not, the sleeve cuff is easily adjustable in the same manner as the collar (that is, narrowing or widening the rectangle by the desired amount). 

Once the bottom of the sleeve is adjusted (if need be), redraft the sleeve edges from the underarm (the widest point of the sleeve pattern piece) to the bottom of the sleeve.

If you widened or narrowed of the bottom of the sleeve, do the same for the hem allowance (the bottom 1" of the pattern piece).

The only other area that might need adjustment is the chest. 

The garment itself is made of stretchy knit fabric and should fit comfortably if worn at an appropriate size, but should it be too tight or loose, there are several simple options to achieve an ideal fit. 

First, as mentioned previously, the center back seam allows for some give and take. 

Otherwise, if the garment is too loose, the body's side seams can be taken in (along with the upper portion of the sleeve seam) after it is already made. 

If it is too tight, extend the upper side of the pattern piece (at the underarm) by ¼ of the desired alteration on both the front and back pattern pieces, and widen the sleeve's underarm edges by the same amount (so the seam lines will match). For instance, if you need the garment to be 1" looser, add ¼" to the top of the front side seam (underarm), ¼" to the top of the back side seam (underarm), and ¼" to both sides of the sleeve underarm.

If you constructed the fly onesie and the leg holes are too large (I, for one, have skinny little chicken legs), you may wish to adjust them.

Model: Alex Beard

Rather than attaching the leg binding stably, you might want to stretch the leg binding as you go. 

This will elasticize the leg holes somewhat and they will be more likely to sit snugly around the legs (such as men's briefs might). The more you stretch the leg binding, the more it will contract around your leg (just like sleeve cuffs do around the wrists).

CONGRATULATIONS!

YOU'RE FINISHED!

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