A few simple rules for riding an elevator:

1. Don't fart. Seriously. I shouldn't even have to list this one.
2. Inside voices. You're in a 8'x5' enclosed box at best, you don't need to yell at the person standing next to you.
3. There's a reason why cell phones don't work well in elevators, and it's the same reason they don't work in planes - because whatever deity you may or may not believe in designed it that way as to not completely annoy people. Therefore, don't walk into an elevator yapping on the phone and then yell "HELLO? HELLO? CAN YOU HEAR ME? I'M IN AN ELEVATOR! I THINK I MIGHT DROP THE CALL! ARE YOU THERE? HELLO?"
4. Let people out before you get in. It's best to let the small, enclosed box empty out first and then go in, rather than shove twice as many people in the enclosed space.