Fulltilt also has color codes for other players. I just use a simple color coding:
green=loose
red=tight
purple=calling station
yellow=soild player
dont ask me how i came up with these colors they are just what I think of when I think about different kinds of player. Also its good to keep it simple because there are alot of colors that look the same. So if you cant tell a tight color from a loose one you are going to have some problems
