I learned this great tip from Tim McCreights “Complete Metalsmith”. In order to organize your sheets of sandpaper and to provide a solid surface for sanding, cut out three pieces of Masonite or Plexiglass 12 inches x 10 inches (or purchase from a hardware store). Mount the sandpaper on the front and back of each board using a spray adhesive glue. Organize by course, medium and fine grit. You can also drill a hole in the corner of the sanding boards, tie them together and then hang them on the side of your bench. Your sandpaper is now organized to sand your pieces on incrementally finer grained sandpaper.