I use one of those suction things you can buy for bath tubs to hold on to. I put that on my 6 x 24 inch ruler and it does not slip around when I am cutting. I also have some little round rubber thing on the back of my rulers . These thing really help. Donna Jordan who has a fabric store in Oregon uses a weight that you exercise with and puts that at the end of her ruler to keep it from moving. Good luck and press the fabric after you fold it so it is nice and flat.