Just read the posted rules, you should be perfectly fine. Like others have said, the biggest faux pas you could commit is disregarding one of the posted rules. Other things that you might want to keep in mind that won't be posted:
1. Know the terms "Cold" and "Hot" and don't call a hot range "cold" just because you arrived and want to put up targets (outside ranges only). I usually take some time to get organized, look around for a natural break in the shooting and then politely ask if we can go Cold.
2. Don't ever cross the firing line FOR ANYTHING during a hot range. I don't care if you dropped your new $10,000 machinegun - don't go pick it up!
3. Try to space yourself out so that your spent casings don't hit the guy shooting next to you. Or, if the range is crouded, then take turns shooting.
4. Don't shoot the ground. Don't shoot over the berm. Or if you are inside, don't shoot the ceiling. Sounds stupid, right? Look at the ceiling sometimes in an indoor range.
5. Don't try to chit-chat with someone who is shooting.
6. If there is a Range Officer (RO) Listen to him and don't ever argue with him.
7. Pay attention to whether or not you are on a range that permits rappid fire. I personally hate this rule, because I always engage in rappid fire when I'm shooting.....but, that's why I only shoot at the plinking range where this is permitted.
8. Keep the muzzle end of your gun down range AT ALL TIMES, loaded or unloaded, or resting on a table, unless it is encased. Don't turn around with gun in hand and "sweep" everyone who is between you and whatever you're looking at that isn't a target. You'll be ripped a new one if you ever do that!
9. Know how to deal with a FTF (failure to fire). In a revolver, keep the gun pointed down range for at least 10 seconds before you rotate the cylinder. In a semi-auto, just keep it pointed downrange for 10 seconds before you eject the bad round - then know where you are supposed to dispose of bad rounds safely.
10. If you bring a kid with you: a) You better know the rules backwards and forwards and be a somewhat experienced shooter and, b) have complete control over your kid at all times. Nothing bothers me more than when I see an adult who has hardly ever shot a gun trying to instruct his kid how to shoot. It's like having the blind leading the deaf, blind and ignorant while bobbling a hand grenade.
11. Don't EVER pretend to be an expert and tell someone else that he's not holding the gun properly, not standing correctly, not shooting properly, or that his gun is no good or junky. As long as the person is being safe and following the rules, tha's about the most annoying thing someone could ever do. Now, if you are one of the noted experts, unsolicited instruction can still be annoying, but occasionally appreciated.