You can put different things on the back of rulers to help them not slip. I usually use the little sand paper dots on the back of my rulers. I have the June Taylor ruler too, and I love it. I have arthritis too, and it helps me not get so tired. I am going to try the Martelli ruler, too.
The June Taylor ruler is pricey, but shop around or use a coupon. It is so worth it. Just zip, zip, zip, and your done. Hope this helps you. Gina