Prerequisites:
If you're fat, don't crowd surf.
If you're big and heavy, don't crowd surf.

Preperation:
Take shoes off.
Put clothes on. (people don't really like holding people up by their sweaty armpits)
If you're over 150lbs, lose weight, repeat.

While crowd surfing:
If you didn't take your shoes off, then keep your feet in the air. That way you don't end up grinding your shoe accross my face or ear.
Keeping your feet up in general is a good idea so you don't kick me in the back of the head causing me to smash my nose against the chick in front of me.
Try and aim yourself to move to the back of the crowd, people are either trying to "dance" with the chick in front of them or watch the band play- not looking behind them for idiot crowd surfers.
It's advised not to crowd surf belly down- this goes for guys and girls.
If you've been "up" several times and keep falling down, stop trying. You're either too heavy or there's too many middle schoolers to support your weight. Everytime you fall everybody around gets pushed (even harder) into the person next to them.

For the people not crowd surfing:
Try and push the person to the back so people can see they're coming.
If some 300 pound dickhead continues to kick people in the face, fall down, get back up, kick people in the face, fall down, etc- don't help him up again, politely say, "I don't think I can lift you".
If some other dickhead continues to help the other dickhead up, try and aim him into the mosh pit. Falling smack dab in the middle of 5-20 kids beating the shit out of each other is a nice way of saying "maybe it's time to stop"