"From time to time people express amazement at how I can get so much done. I, of course, aware of the many hours I have idled away doing nothing, demur. It feels like nothing special; I don't work harder, really, than most people. Nonetheless, these people do have a point. I am, in fact, a fairly prolific writer.
"Part of it is tenacity. For example, I am writing this item as I wait for the internet to start working again in the Joburg airport departures area. But part of it is a simple strategy for writing you essays and articles quickly and expertly, a strategy that allows you to plan your entire essay as you write it, and thus to allow you to make your first draft your final draft. This article describes that strategy.
"Begin by writing - in your head, at least - your second paragraph (that would be the one you just read, above). Your second paragraph will tell people what your essay says. Some people write abstracts or executive summaries in order to accomplish this task. But you don't need to do this. You are stating your entire essay or article in one paragraph. If you were writing a news article, you would call this paragraph the 'lede'. A person could read just the one paragraph and know what you had to say.
"... there are four types of discursive writing. Each of these types has a distinct and easy structure, and once you know what sort of writing you are doing, the rest of the article almost writes itself. The four types of structure are: argument, explanation, definition, and description. So, as you think about writing your first paragraph, ask yourself, what sort of article are you writing. In this article, for example, I am writing a descriptive article."
Via Jim Lerman