The idea of “flow” is an interesting one. Being in the one spot where everything is going perfect is the Utopia we all strive for. Many people never achieve such “enlightenment,” but I would like to think I have come close. I think the closest I have ever come is playing music. When you are on stage playing songs that you wrote, for complete strangers and looking out to see they are actually enjoying it is a feeling like no other. I think of it almost like muscle memory. You get into the flow and you can’t afford to think about anything else. You have to trust yourself and trust that the other guys in the band will play their part so everything comes together. When you find yourself worrying about making sure everything is perfect, then the flow is gone.
In design I am not sure I have achieved this flow, but I feel that it works exactly the same. You have to learn to trust yourself and what you know.