In California, our local desert museum had an exhibit on Rattle Snakes (and other desert creatures) that was amazingly interesting.
Just as Desert Captain mentioned above, don't cut yourself or try to suck out the poison, you will just get the poison in your mouth. Don't use a tourniquet as you are concentrating the poison in just one area and restricting blood flow which is something that you do not want do. It was said that it is better to let your body dilute it through your system than it be concentrated.
The number ONE thing to do when bitten by a snake is get to a hospital ASAP! And, if you can, determine what type of snake bit you. If at all possible, hopefully, bring the killed snake with you (slim chance right?) so that the doctors will know what type of antivenin to give you.
I've seen 3 rattlers around the house in 22 yrs. and one King Snake (those are good to have around as they kill rattlers). Rattlers do not want to be around people. So, when I go to get fruit off of the trees, I walk like an elephant stomping my feet to make them aware that I'm around. :p
Safe travels,
MM.