Chan Geer taught me to lay some clear plastic wrap (comes on a roll for your kitchen) or clear plastic bag (opened) over the cased leather .. this will keep your pattern dry. Use a different color pen so you see what is done. Be sure to glue down your leather with rubber cement (i use Xray film) or use sticky one side shelf paper to avoid stretching the leather as you pound. Good luck stan from saskatoon SK canada www.stangarchinski.com