1) Sit on the toilet then get up and say look more sinkers that floaters!
2) When you are sitting on the toilet and someone is in the stall next to you look under and say do you have any toilet paper that i can borrow. If you want i can give it back when i'm done.
3) While washing your hands constantly flick a little bits of water at them until they leave or tell you to stop.
4) Grunt and act like you are straining until the other person in the bathroom gets disgusted and goes out.
5) While sitting on the toilet hum to yourself and then ask anyone that is in the bathroom if they have a magazine that you can borrow.