When you have an idea for solving some problem or doing recreational stuff with the board, how do you go about planning for it?

I'm making a RGB LED that can be controlled with a button interface and a potentiometer. Practically useless, but I wanted to make something with my knowledge of 1/3 of Paul mcWhorter's new arduino series and I'm having fun manifesting thought into reality. My issue is that I went in headbutting it with minimal thought or planning for the project, I know what components I needed and I had thought of a rough idea of how it supposed be.