I have used some precuts, when traveling & ran out of ones I cut myself. I mainly use the cards that come in magazines, you know, the ones that pull out & want you to subscribe. They are free & work great! Hadn't thought of file folders either, another good idea. I also cut squares, then trim them down as I stitch around the hex, & don't stitch through the paper, just double stitch at each crease around the edges & that will hold it, & make you papers last longer too... Love projects like this, enjoy!