It used to be a bit of a problem for me to tell where the lines were, then I grabbed one of their half-size (ruler width is not an even number. I used to use a 6" ruler, now I use the 8 1/2" one) if that makes sense. With the "half" ruler, the thin line is the one that lines up with the edge of the fabric instead of the thicker yellow or green. I do have a circle template that almost glows it is so fluorescent green --- I can see the marking perfectly on that one no matter the color of the fabric.