Whether you are dressing up as a weightier superhero for Halloween or you need a costume for a theatre production, fashioning yourself a realistic-looking fat suit is a fairly straightforward task if you have the right materials on hand. In designing your suit, pay attention to detailing that adds realistic definition to the girth, rather than opting for just a "pillow" effect. Keep in mind that as hilarious as you might find yourself looking in your fat suit, weight is a touchy issue for some, so try to be aware of those around you while wearing it.
Take one of the T-shirts and sew the bottom hems together.
Reposition the shirt under the sewing machine and sew a line from the shoulder area of the shirt down to the bottom hem---do this on both sides. Cut off T-shirt sleeves.
Repeat the above steps on the second shirt.
Stuff both shirts with washable cotton filler up to the neckline. If you wish to add pectoral muscles or other definition, simply sew a seam below the area you want to define and fashion the filler around it.
Sew the two neck holes closed (separately) on both shirts. Sew the first shirt to the second at the shoulders on each side of the shirts. Be sure to allow plenty of room for the person wearing it to easily slip his neck through it. Sew the sides of the shirts together approximately halfway down the shirt. It is not necessary to attach the shirts all the way down the side, but you may if you wish.
Add heft to butt and thigh areas by cutting pantyhose pieces into 3- to 5-inch swatches (when material is relaxed). Sew one end and lightly stuff with filler before closing up the other side. You can tuck these little pouches and adjust them to add additional girth where needed.
If you need extra weight in the arm area, use long-sleeved T-shirts and stuff them to the wrists with filler, sewing each T-shirt closed at the wrist. Tuck the sleeves through the top and bottom of the shirt sleeves you will be wearing over the fat suit when dressing. Add less filling toward the neck area of your fat suit to avoid an overstuffed appearance. You may attach Velcro on the sides to attach the shirts, instead of sewing them tight, if the suit will be used by more than one person. This lets individuals of different sizes utilise the suit.