Cut down a plastic grocery bag to create a single sheet of plastic. Place plastic sheet over cabbage.
Apply strips of masking tape to plastic, overlapping each slightly, until you have formed the shape of a skull cap. Add two to three more layers of masking tape to create a firm wig base.
Remove cap from cabbage, and trim excess plastic around cap. To add extra support, place a few strips of masking tape around the edge and inside the skull cap.
Place cap back on the cabbage and begin styling the wig. Cut colored paper or newspaper to 1/2-inch strips, or cut lengths of curling ribbon to create hair. Curl "hair" by carefully dragging across the closed blade of a pair of scissors.
Add 4- to 6-inch strips of double-sided tape to the bottom rim of the cap, and begin adding hair. Continue adding more tape and "hair" strips until you reach the crown of the cap and the wig is full.