What is a one-sentence summary of the following article?
Cut along the sides of the duct tape to even out the edge. Use a ruler to help guide you and make a straight edge. Don't cut too much off, as that will make your wallet too small. For a shorter wallet that will more snugly fit skinny American dollar bills, make your rectangle no smaller than 6 by 8 inches (15 by 20 cm). Cut pieces of tape that are the height of the sides of the pocket you've just made. Place a piece on each end, folding it over the cut edge and around the back. Smooth it out with your fingers. The edges should be up against each other when you wrap the tape around them.

Summary:
Trim the edges of the duct tape. Tape the edges closed.