When you sit down to write, consider for whom you are writing. If it is a scholarly piece of writing, you want to address other scholars. This audience would have a similar background and a knowledge base that allows the reader to come to your writing at a certain level.
If you are writing for a more general audience, you need to give more background on what you are writing so that the masses can understand the material as some will not be coming to your writing from a scholarly point.
Sometimes you may be writing for a mixed audience that would consist of both experts in the field and a more general public. This audience is more difficult to address in your writing, as you need to keep a balance to make sure you are appealing to both audiences and that both audiences can follow your argument.
Whoever your audience is, keep your audience in mind when you are writing. When you go to revise your work, ask yourself if your audience will be able to follow your line of reasoning. Ask a coach to help you make sure your audience can relate to what you have written.