We probably have, at some point in our writing careers, had somebody come out and shake the red pen at us and cry, "format, format, format!" I even know of one person who claims to format as she goes.
Well and good, I suppose. Formatting has its place, do not get me wrong but a first draft is all about getting the words out of your head and on paper. Creativity does not breathe in a box. I notice that when I start becoming concerned about formatting as I am writing, the process shuts down. It becomes mechanical, dry, passionless.
I don't want to write that way. Do you?
Now having said that, I don't want anyone to perceive that I don't know there is discipline in writing because I know there is. You have to do it often, every day is best, you have to push through barriers and keep your thoughts and stories alive. The point is, do not worry about having perfect sentence structure or proper margins or starting every new chapter halfway down the page. Do open your mind and let what's in your mind flow out onto your medium, paper or computer screen, whatever you are using. Let it flow. When the appropriate time comes, you can and should and will go back and refine.
Get the words out of your head an on paper.
Just do that and in time, you will find your rhythym.