I have spent a good part of my career studying successful people, in all walks of life. One thing that these successful people have in common is they all have coaches. Pitching coaches, life coaches, music coaches, business coaches, academic coaches, etc.
Nobody can do it on their own. A coach can see things the player/client/student cannot.
Learn from your coach’s experience.
And when your coach isn’t around, coach yourself. Pick yourself up instead of beating yourself down.
“You can do this!” is better than “That was a stupid thing to do!”
Fire that negative coach in your head.