The first thing the reasonable man must do is to be content with a very little knowledge and a very great deal of ignorance. The second thing he must do is to make the utmost possible use of the knowledge he has and not waste his energy crying for the moon. The third thing he must do is try and see clearly where his knowledge ends and his ignorance begins.
Peak performers develop powerful mental images of the behavior that will lead to the desired results. They see in their mind's eye the result they want, and the actions leading to it.