I have done pping and I have just used my good old trusty regular ruler for trimming. I would recomend getting one of Carol Doaks books from the library. especially one with a cd in it. This will show you how to pp the really really really easy way. I would do one block pp'ed with a regular ruler as long as you can see a 1/4" mark on it really well. if you have a small thin ruler like a 2 1/2x 6 1/2" that would do the trick to start with. but any ruler would work. ask for an internet video I don't know of any. I just used the CD from Carol Doaks book on PPing stars. Good luck and post your finished block.