As seen in the "Pitch Your Project" Thread, the users of MT seem to have lots of different ideas for comics and manga. However, it seems that very few of us ever really try to work on these projects more than a few scattered drawings of the characters. (Exceptions go to Reg and Cake. Keep up the good work, guys.) With that in mind, how exactly does one take an idea and grow it in to a full length comic?

I've personally written a one shot two or three times, but I feel that is a lot easier. When thinking about full series, I generally know what I want for the first few chapters, and what should go on to get the story to it's end, but filling in the middle always seems hella difficult. How do you guys think that should be done?

(Think of this thread as a continuation of the PYP Thread, where users try and help you get in to your comic's progression and get it moving.)