With your newly gathered used tin cans, remove labels, and clean thoroughly. Fill each can with water and freeze overnight until solid. The ice stabilizes the can and prevents it from bending when you punch holes in them later.
Cradle the frozen tin can in a folded towel (to prevent the can from moving and to catch ice chips). Position a sharp, narrow nail above each mark on your pattern and gently tap it 3-4 times with the hammer until just the point has punched the tin can. Repeat for each mark until you have completed your pattern.
Rubbish-art 