Want urinal etiquette? Here's what you don't do.
Don't walk into the bathroom and start speaking with the guy peeing. He's not your best friend, he's there to pee and wash his hands.
Don't choose the urinal right next to someone when others are available. This is very creepy. You are expected to keep your distance because personal space becomes even more precious when the pants are down. Look straight ahead and do your business. You didn't go to the bathroom to chit-chat so leave your anecdotes at the door.
Don't touch your wang unless you're at the urinal. When you're done, zip up and put it away. Always do this before turning toward the sink. No one in that bathroom wants to see your penis so hide it in your pants where it belongs.
Try not to poo in a public bathroom. Due to odour issues, pooing is best done at home or in the bathroom of a close relative. If you can't avoid it, do what you must. There are medical consequences to holding off too long, but hold off as long as you can.
Don't go to the bathroom in a group. Women may do this, but you don't. Going by yourself is more efficient. There's no gossip, no "do I look alright?" and no "do you think he likes me?" You're a lone rider--you do not need your flock to go to the bathroom with you.
Don't make a mess. People clean up after you so make their job as easy as possible. Aiming is pretty easy, whether it's with your wang or with your paper-towel jump shot.
Don't sing, don't dance and don't masturbate. Try not to have sex in the bathroom either. (Airplanes are an obvious exception here, but not one that should be abused.) Do not get into "who can pee further" contests. While fun, these are best done in Mother Nature's backyard.
All in all, use your common sense. Treat the urinal with respect and you'll be fine. No accidents, no fights and no peeing on the floor.
The above is declared null and void if you are drunk.