Dress up plain flip flops with paracord. Use the same method that you'd use for a bracelet, but use the strap of the flip flop for the center. The tutorial in the attached link shows how to make them by completely removing the strap.
to aprons This is another interesting and funny way how to use old jeans. Take one trouser leg and cut it in apron shape. Take some other old fabric, and cut it in thin ribbon. Sew them together to get aprons from the old jeans as shown bellow.