I have done a lot of ruler work quilting on my DMS. I purchased quite a few rulers from
sewsteady.com their Westalee rulers mostly. They have so many shapes etc. I have used their: Spin-E-flex rulers, echo templates, and Circles on Quilts rulers, among other rulers they offer. I also have purchased rulers at
quiltersrule.com I really like their different shapes and sizes of their rulers.
I usually practice on a few scrap squares first and then making sure my quilt or quilt sections are well supported it isn't really difficult. Even doing a full quilt, you are only working on one section/area at a time, and then moving onto the next area after you do the spiral or shape you want, so even with an entire quilt, as long as the weight of it is supported so the area doesn't slip more than you need it to move, it fairly easy to do, after a couple or few practice runs on the shape/design you want.