Single pin sight?
 

I'm looking into a single pin sight primarily because my eyesight is aweful and not getting any better. So if I understand there are sights that slide up and down vertically and I guess lock into place? On these sights I've also noticed stickers with numbers how exactly do you begin to sight this kind of sight in and do any of u guys use them? I noticed one on eBay I think it said it was totally tool less it looked like a neat idea

they make programs that you enter all of your bow and arrows spec's and you can print out the tapes with the yardages. or you can do it the manual way and just put a blank tape on your sight and start shooting. all you do then is take a pen a draw a line where each yardage you want. they do come with some pre marked tapes for reference but each bow is different. it all varies on your bows speed.