If you're about to take a test or go on stage or do something really challenging and really important, how do build confidence and convince yourself that you will succeed? "I want to believe that I can do this..."

Let's say it's an audition or a standardized test or something that's impossible to be 100% prepared for. You still want to believe in yourself.

(In the way that I operate, this is related to anxiety. I didn't explain because that discussion will likely work against me in my circumstances. I'm battling performance anxiety.)