I just took my 6 1/2" square ruler and used 1/4" tape to mark the lines at the angles needed to make the twister. This can be done on any size of square ruler. I also marked on the tape with a pen a small arrow so I used the same side of the tape so all cutting would be the same. When I am done I can just remove the tape. It is the 1/4" quilters tape. I got 3 rolls for 50 cents a roll on clearance at Walmart. I have also used the tape to make other designs on basic rulers like wedges and wonky squares and visual openings for fussy cutting.