I use a Gripper handle. I'm not sure the brand name will try to look for you. I bought mine at LQS but I've seen similar products at Bed Bath and Beyond and Wal-Mart. I think my ruler has some pads on the bottom of it to prevent slipping too. Others have mentioned these pads as well. Hope you find something that works for you. I know from experience that this is a frustrating problem to have.