Singing, humming, and whistling are generally discouraged.
If you're only going up or down one floor, use the stairs.
Always stand facing the door.
If you're in a crowded elevator and have to leave, announce that it's your floor and excuse yourself.
Answers: 1. Once the Doors Close (duh!); 2. Calling and Waiting; 3. Boarding; 4. Exiting
We admit that number 3 is kind of tricky and easily falls in the Once the Doors Close category. We also admit that we occasionally break the "no re-pressing the floor button" rule. (in Society & Culture)