First you need to figure out how wide your torso is. For the armor in the first picture we cut our pieces 18 inches long x 8 inches wide for the two top pieces and 18x4 inches for the lower eight. You will also need another two 18x4 pieces for the shoulder straps. It is important to not make the pieces too wide and to mark them all out on the sheet before you cut in order to make sure you have enough sheet metal. I would probably not go over 20 inches wide for most anyone. It is easy to cut once you have the pieces marked out. We used a square to mark everything, but a ruler will work just as well if your careful to keep things square. Use the kitchen shears to cut out all your pieces at once.