Cut the bubble wrap so that it is the proper length. Hold the bubble wrap against the cast to measure. Then, using your scissors, cut the length and width of the bubble wrap accordingly.
Wrap the cast with the bubble wrap, enveloping it completely. Depending on the thickness of the wrap, you may need to go around the cast several times.
Secure the bubble wrap with packing tape or medical tape. Run the tape along the outer seam of the bubble wrap so that it is secure on the cast.
Cover the bubble wrap by wrapping the elastic bandage over the entire surface. Be sure to overlap the bandage as you wrap in a tight manner. Many elastic bandages now have a self adhesive surface. As you wrap, the elastic bandage will secure itself on top of the bubble wrap.
Secure the elastic bandage by using a piece of packing tape or medical tape along the final piece of bandage. The self-adhering elastic bandage may lose stickiness from sweat, dirt and other elements during the game. Adding tape will prevent this from happening.