I bought some Fiskar's clear stamp sets (the ones that are on a whole sheet about 8 1/2 x 11 size). The directions say to use something called an Easy Stamp Press or clear blocks, but I don't understand how the stamps stay on. Do you attach them permanently and what do you use to attach them? Or, are you able to interchange them -- this is what the directions elude to, but I don't understand how they stick. Can someone help? Thanks, Carol