Soak the leather for an hour, then wrap it or place it in a ziploc bag overnight. It will be soft and pliable after that. Wrap up your piece (pistol / knife) with Saran Wrap to keep it dry and form the leather around the piece, pressing with your fingers to form it. As it dries (usually a couple of hours) keep pressing from time to time. Then let it dry fully for a day or two. I've also heard some folks soak with acetone and form immediately, but I've never tried this. Hopefully one of the more experienced guys will chime in with corrections or more tips!