Question?

Through all of the tutorials, I am learning a decent amount about Flash and how it works.  However, I do have a question (which is quite convenient considering comments are a required part of the course).  When do we actually begin designing the game?  So far I have made about twenty different tutorials about my game but have yet to actually design more than a few scenes.  This is an open question, and if any reader could assist me with it, I would be most grateful.