Halthron:Wander around enough underwater so that you get a bit of water at the bottom of your mask then do a backflip*. Using your nose for breathing or not, the water goes up it! It didn't take me long to learn to clear my mask before flipping.
*If I'm careful, I can do a front flip without snorting water.
Teehee, I was doing a handstand underwater last week and got a bunch of water up my nose and then had a difficult time getting my mask to clear cause of all the snot! What a mess. It made me realize that my mask is really leaking alot, the silicone on it has warped with age. Time for a new mask, and next time I do an underwater handstand I will clear first!