I like to use old phone books, the paper is easy to tear off and I can get an 8" square out of most of them. If you want something bigger, you can use OLD newspapers. I say OLD because the newer papers could cause ink transfer but the older ones the ink has set in and they are fine to use. Also an old thin sheet cut into squares works well, but I prefer the Paper. You can also inquire at your newspaper office for roll ends of newsprint paper as they often sell them cheaply and a small roll lasts a long time.