The hole punches Dave mentions are good to have for numerous reasons (fender welt holes would be one other example). However if you don't want to invest in a set (violating the man code of "...any excuse to buy a new tool") you can make your own. A piece of pipe ground to an circular edge (for those having trouble visualizing that think circular chisel) at one end. Punch the webbing on a block of wood to preserve the ground edge.