Let’s begin with the immortal words of Virginia Woolf: “To know whom to write for is to know how to write.” When deciding how to write something you are deciding who to write for, and once that decision is made everything else follows. Once you have decided what you want to say, the how follows from the who, at least in principle, if not always in practice.
Now, in academic or scholarly writing, you should always be writing for a peer, so imagining your teacher or your editor (or Reviewer #2!) is simply not going to work. Examiners and gatekeepers are not, properly speaking, your readers; but both are trying to decide whether your actual reader will find your writing useful, and they will judge your work on that standard. So you have to imagine someone who is roughly as knowledgeable about the subject as you are, someone in your class or discipline that you consider an intellectual equal. As I sometimes put it, don’t look up to your reader and don’t look down on them; pick someone your own size and look them in the eye.
Consider the difficulty you are presenting the reader with. Will your reader find what you are saying hard to believe, hard to understand, or hard to agree with? (Alternatively, is your reader bored?) This is an important decision — a fateful one, we might say — because it will determine your rhetorical posture — will you be supporting, elaborating or defending what you decided (yesterday) to say.
Do imagine yourself adopting a kind of “stance” and imagine your reader facing you in the complementary position. If the reader is likely to doubt your claims, be ready to offer support for them. If the reader is likely to misunderstand you, be ready to elaborate on what you mean. If the reader is likely to reject your view, be ready to defend yourself. Some people imagine this as a boxing match, or at least some light sparring. But if you don’t like fighting (even figuratively), feel free to imagine yourself and your reader as dancers. Remember, however, that it’s not all about the knock-out punch or the big dip at the end. It’s about lasting out the round, maintaining your grace throughout the whole number, and having enough strength left over for the next.
Let’s consider your reader’s situation. In most cases, you are going to be composing a paragraph of no more than 200 words. This means you have about one minute of your reader’s attention to work with, and this minute is part of a series of minutes that you are also in complete control of. (Except for your first and last paragraphs, you have just occupied the preceding minute of their experience and you propose to occupy the one that comes after as well.) You have to respect this constraint on your reader’s time. Except under very particular circumstances, and only to accomplish a very deliberate literary effect, do not expect your reader to read your paragraph two or three times. Imagine you only have their attention for one minute and that they’ve already spent as many minutes in your company as you’ve given them paragraphs to read.
Take stock of your resources. First of all, you have much more time than the reader. An ideal writing moment lasts 27 minutes and is followed by a 3-minute break. You are 27 times stronger (or faster, if you like) than your reader. You are writing in “bullet time”. More importantly, you are writing from the center of your epistemic strength, presenting justified, true beliefs that you are able to converse intelligently about in person. The paragraph you are now writing is just the tip of the iceberg of your knowledge, and it will have the dignity of everything that lies. unseen and unsaid, below the surface. An important part of the “how” of writing is experiencing yourself as knowledgeable, as solidly grounded in the literature, your experience, and your reasoning — everything you have read, everything you have seen and done, and everything you have thought carefully about. You have chosen but one of our many ideas that are as solidly well-founded as this. Write with the confidence that this choice gives you.
At the end of the day, writing well means choosing the right words in the right order, to help the reader overcome the difficulty of what you are saying. You want to put the reader on the same solid footing you have for believing what you are saying to be true. This will also give them a way to understand you and, of course, a way to disagree with you. That’s what academic writing is for — to share our reasons for believing things, so that others may understand us or challenge us as they will. Remember to conserve your strength, which is to say, don’t try to put all your ideas in a single paragraph. This is one round of what may be many. The night is still young.