The best way to make your own targets

After experimenting with a handful of ways to make USPSA targets, I think I have found the most efficient. Clamp cardboard sheets together, cut them out with a jigsaw, and use a template to spray-paint the lines on. If your cardboard sheets are all roughly the same size, you can make ~50 targets an hour with this method. If you know a faster way, please let me know! I'd love to make this process even better.