Prewriting:

"If I am right - and I know I am - you go about any writing job piecemeal, slowly formulating a sentence and putting it down on paper, then stopping and thinking, preparing the next sentence in your mind, putting that down on paper, pausing again to think of what to say next, slowly formulating another idea, writing it down, stopping again, rereading what you have written, working up the next sentence, thinking it over, searching for a transition, hesitating, inserting a qualification, writing again, stopping, thinking, searching for word ... etc., etc., ad infinitum. It's writing, after a fashion, but it's as different from the real thing as drafting a speech sitting alone at your desk is from addressing a roomful of people.

So you have to get used to the idea of 'prewriting' - doing research, taking notes, organizing your material - and then writing, at an even speed, keeping up a flow of talk to your reader without any awkward pauses or hesitations."

Rudolf Flesch - How to write, speak, and think more effectively