I have tried many different tools and, to date, the best by far is a thick (clear) plastic ruler and a sharp, snap-blade box knife. They are both inexpensive and deliver sharp, accurate results. For even better results, use a piece of glass or mat cutting board to cut on. *Tip - Always keep your ruler or straight edge to the left of the cutting blade and cut the plates on the right side of all 4 edges. This method will ensure you have no ridges or hard edges on the good section of the plate.