After three years of solid yoga practice, I've come to realize a lot of my progress derives from a willingness to play on the mat.
The only way you'll get to a point where you're willing to risk falling on your face in front of a crowded studio... is when you let go of the fear of making a fool of yourself.
Try out the pose.
We're all just playing when we come to class.
When you fall, laugh. Learn how to fall safely so you don't get hurt.
But more importantly: be willing to fall. :)