I do not know if you are asking about the post notes as a guide or just fo many hints, but I sent the one about using the post note, I was working on a project and it was a dim day and I was having trouble seeing the line on the ruler. I am a senior citizen) and I just happened to have a post note pad and thougt it would work if I just cut off the sticky part and put it on my ruler, I love the way it works especially the yellow one it is very visible.
Hope this helps.