This is fucking hard.

OITE - 14

When someone gets on the elevator. Pull out your camera and ask your friend.
"Hey, you want to see a video of me fucking a hooker?"
Then let your friend watch for a minute.
"Tricked you. That's video of me masturbating."

These get grosser as I try to come up with them.

15:
The second the elevator doors close shove your friend into the wall of the elevator. Then proceed to wrestle violently as the elevator goes up. Pin your friend and yell at the stranger:
"Come on! Count him out! I need a count!"
As they avoid eye contact yell:
"One, Two, Three! Come on. You're gonna cost me the belt here!"

16:
Just calmly and without saying a word trade pants, shirts and shoes with your friend while the stranger rides.