Cut the shorts, dip them in bleach, and use fabric paint for a pattern!This will probably be my last shorts pin of the summer. I would work with jeans as well though going into fall. You could bleach up to the knees for example.
DIY tank top - item: scissors, bleach, plain tank top/t-shirt. Dip dye the bottom of the shirt with bleach. Wash it out and let it dry completely. Then cut the part you bleached into thin strips and tie a knot at the ends.