How to Make Jeans Tighter. Tight jeans are flattering to many body types. And when jeans are too big, they can be shrunk to make them tighter for a better fit. Making jeans tighter can be done either with a sewing machine or with a washing machine and dryer. To change the size significantly, use both methods.
Set the washing machine to the hot water setting. Wash the jeans on a long wash cycle on hot. When the cycle is completed, dry the jeans with the longest, hottest drying cycle. Continue the dryer even after the jeans have been dried. This will make the cotton shrink as much as possible. To get more natural cotton shrinkage, repeat the washing cycle two or three times before drying.
Make the jeans tighter with a sewing machine. Flip the jeans inside out and lay them flat. Choose a thread that matches the thread used on the jeans.
Use the sewing machine to change the seam. You can start at the bottom of one leg or at the crotch. Follow the line of the seam on both legs and at the crotch, sewing slightly inside that line to make the jeans fit tighter. The further from the original seam you sew, the tighter your jeans will be.
Check the fit to see whether the jeans are tight enough. If they aren't, turn them inside out again and make the adjustments. If only one part of the jeans are too loose, concentrate on just that part. If the jeans began with flares, sew on the lower portion of each pant leg.