1. Remove labels, tops, and bottoms of 26-ounce tin cans. Use an old-fashioned beer can opener to make triangular holes around the perimeter of the top and bottom of each can. Wear work gloves and be careful with sharp edges.
2. With a hammer and sharp nail, carefully punch additional holes in a pattern on the surface of each can. Aim for a simple, stylized pattern. Work with a spare can or two for practice, if desired.