If you have an old T-shirt with a great graphic but a bit too much damage for regular wear, you don't have to trash it. Recycle it instead. You can transform that holey T-shirt into a great pair of sassy undies if you make the best use of the salvageable fabric.
Wash and dry the T-shirt.
Cut the T-shirt apart along its existing seams and then lay all the separate pieces flat.
Cut out the pattern pieces as indicated in the manufacturer's directions.
Determine whether the T-shirt's graphic is a better size for the back of the underwear or for the front by holding the respective pattern pieces over it and pinning the best choice in place.
Pin the rest of the pattern pieces to the T-shirt fabric, avoiding torn or worn places.
Cut the T-shirt pieces.
Sew the pieces together as directed in the pattern you chose.