Proper way to use the swiss ball?
 

I just borrowed a swiss ball from my cousin and I was wondering what's the proper procedure to do ab excercises on them for the best results? Am I supposed to put my buttocks on the edge of the ball and rest my back on the rest of the ball with my feet at a 90 degree angle? Then do crunches with my hands behind my head (no interlocking) and do a couple of sets? The first time you use the swiss ball are you supposed to have some stability or balancing problems? Because I fell off of it backwards and hit my head on the floor. :(

there's a TON of "proper ways"
all of which are extremely hard to descripe properly with words
you need a chart to look at which can show you how to do the different exercises

Do you know where I may find this chart?

hmm no I guess I don't

I know some of my friends got one with the ball that they bought..and in my gym they just have a bunch posted on the walls next to the balls

What about just for crunches?

Well, besides a GIANT GAME OF FOUR SQUARE, the swiss ball can be used for a lot of exercises.
http://www.jumpusa.com/swissexercises2.html
Most people are going to want you to but a video to properly use the thing. Ask your trainer, physical therepest, or doctor.

Google is your friend. Try "swiss ball exercises".