Read the Chip Reese section on 7CS in S/S. Use it as your bible. Todd Brunson wrote a section on 7CS Hi-Lo in S/S 2 also, which is useful (but no where near as great as Chip's writeup from '78). Agree with yawwn about the rake too. I'd start playing the high variant then transition in to the hi-lo once you move up to mid stakes.