I was going to suggest the tiger tape as well. As QuiltnLady1 says, there are different measured markings so pick one that is comfortable to you. JoAnns carries the product so it's easily enough gotten (provided you have a JAF near to you) and is quite affordable. I'm not sure I'd want to mark my nails with a sharpie. Although you could probably also use a sticky note with markings as well. Stick to the backing of the quilt and move along as you go.