Skills: This is how well you expect them to be in bed
Wankability: This is how easy you would find it to have a wank over them (Sexiness)
Ass: How nice her ass is
Tits: How nice her tits are
You would rate each of these out of 10 then take an average giving you there overall score. Though recently a C has been added making it SWATC. This C represents cuteness as it was thought to be another important aspect.