In order to contain my project, I have created a notebook for it. I find that doing this keeps things organized, which I feel is an important part of creation. The more organized I feel, the better I can concentrate on the content. At least that is what I believe. Is it true? Who knows.
I like to dedicate certain pages to a specific item. One part of me is torn because it limits the amount of space I can commit but also, certain limits can force you to adapt to the space as a means towards moving forward with the work and not getting caught up in one thing. Will I make mistakes? Of course. Nothing is set in stone, only paper.
What kind of process do you have at the beginning? Is organization important to you or is creation at any cost more important? Or is it something completely different?