Anyway, on to the rest of your question. Basically with distortion, it's all about ratios. The more distortion (or "gain") you have, the less volume you should have, to keep things even so that you get a distorted tone and can still make it out. As far as low and high, just whatever sounds good to you, I think.
Maybe there's more to it than that, and if so I'll be very happy to learn.
You go outside and practice screaming. We'll play music while you're gone.
