[Aisthesis]

Patience is my short answer. In a tournament, while you need it, there's a time when patience is over and you just have to move. In a cash game, you don't--which is certainly not to say that you shouldn't "make moves", just that the value of these moves isn't so much defined by your stack-size vs blinds as by table texture.

Aside from that, there's one easy way (definitely not infallible) to spot candidates for good cash game players: big stacks. I've seen very good players, though, with short stacks, and very bad ones with big ones. But most of the time, the big stacks are better players.