To adjust the slide, simply move the thumb tab andpivot either up or down. The yardage markers are bright and easy to set. Even the indicator pin is fibre optic and easy to see. This sight is easy to install. I can build arrows but am just not a bow tech. I had this sight installed in about 5 minutes and in about another 5 minutes was putting 5 arrows in the X ring. For you guys that are looking at new sights, definetly check this one out! The only down side is the price. I got it for cost, but MSRP is around $150. Oh, and it is very light as well. My bow is lighter and quieter than it was with the Easy Slide Extreme. Needless to say, I am one happy bowman!! This is what the thumbtab looks like.