Write twice: once to discover what you think and once to present what you’ve learned. Committing yourself to writing twice may look like a burden, but you’ll probably find it to be liberating instead.
The first time through is when you find out what you think. You can’t skip this; you won’t know what you have to say until you get it out. No matter how many times you read through your sources, you’ll find that your ideas and concepts will always have something ethereal about them until they are sitting on your computer screen.
You won’t want to submit any part of this early version. It will be uncertain here and overconfident there. Your narrative will leave out what’s essential and spend too long going over what’s not. But you must allow yourself the freedom to write in this less-than-perfect way without fear of being judged. Seek out new ideas, discard old ones, and don’t stop to polish phrasing unless you really can’t help yourself.
But this freedom to explore carries with it a new obligation. You have to be ready to throw out all of the mess you’ve just made. Your task will involve more than just shifting sentences about and trimming superfluous words. It’s not good enough to scan through your work for mistakes and call it a day.
Instead, use your second composition to present your discoveries as perfectly as you can. You have to make it as easy as possible for your reader to approach the topic, and this can never be done by summarizing the haphazard process by which you came to understand it. Your finished prose should be cool, precise and polished. This will not be easy to accomplish, but it should look as though it were.
The secret is in carefully visualising the scene. Reimagine your topic, with all of its abstract complexity, as a mechanical object that can be described in an exact way. Now conjure up a reader, an interested and intelligent person who wants to learn about how your topic works. What are its parts? How do these parts interact? How has your topic been used or interpreted by others? Guide your reader’s attention to what you’ve noticed.
This is where student writing fails so often, and that’s a pity. If you don’t take the time to rewrite, you’re acting like a pianist who releases a recording of an early practice session instead of the final performance. Your essay is not a record of how you came to know something. It is an act of communicating what you have come to know.
To learn more about how to do this, see chapter 2 of Pinker’s The Sense of Style and Thomas and Turner’s Clear and Simple as the Truth.