The best advice I ever recieved as a jazz pianist
came from my music teacher
First of all, learn your scales such as Blues scales, major scales, minor scales, etc.
Make your mistakes big and loud. Confidence will work for you, and you may find that your mistake actually sounds good.
Solo at every available opportunity.
Don't think about what you're playing, just do it.
Play as much as possible.
Somehow, I think he was giving me a lesson on life.