I have tried tearing fabric a couple times, and I am not a fan. I know it works for others but I just didn't like how stretched the fabric was and how much I had to trim off.
Peckish the instructions call for each piece to be cut length of fabric 90". If I folded it enough times to fit my 24" mat I don't think I could cut through it, or do you keep moving it to get the uncut portion on the mat?