Easy as pie, I do it for all my homebirth clients. Washable stamp pad from craft store ( I carry blue and hot pink), nice art paper, baby wipes. Press baby feet to stamp pad one at a time to coat completely. Stamp two or three pieces of paper (will be a bit lighter each time). Baby wipe to remove ink from foot fast. I can do both feet in under three minutes. They don't like it much, because they don't like you holding feet that long usually.