I agree with Tartan. They do make fine line Sharpies in different colors. I would see how it works on the back first. I only use the lines to line up. Also depending how old it is and how often you use it get a coupon and buy a new one. Great idea for a Christmas or other holiday present.
Originally Posted by
Tartan
You could try a fine Sharpie on the back and see if rubs off? I think it might bleed over where all the marks crisis cross also? Really can't think of any thing else you could use to remark the lines. You might be able to use a couple of pieces of Duct tape to make a cross on it so you could line up your fabric with the edge. The tape might get sticky after a while though.