First, use the context sensitive help. It has several examples of how it works. A very basic overview is that it's based on Drive, Part, and Check geometry. A very simple ex: You select the Drive surface - the side surface to which the tool will drive along (perhaps the side tool will be profiling). You select the Part surface - the surface the bottom of the tool will cut. Then the Check surface - the surface to which the path will check to (or stop at). There is a bunch more to it but that's the basic format.
Like Tim said, get some classroom training. You paid a bunch for the software and your probubly making expensive parts. There's a bunch to know and by doing it "self taught" you'll really miss out. I've seen programmers blast it for not being powerfull - usually because they were self taught.
--
Bill