For simple shapes that I will be repeating, I also make templates (got some used plastic signs from HD). Have used 1/8" masonite or thin plywood. Found this works better than cardboard as it tends to fray around the edges over time. For more intricate patterns, I apply blue painters tape then glue the pattern (do not like the purple). If cutting a hard wood or stack will apply clear tape over the top to help prevent burning. If I want to combine patterns or put figures together (like initials), I use a light box that I made.