Once the outline satisfies you in regard to clarity of direction, write the topic sentence for each step in the development of the paper. Develop the topic sentence of each individual section. Every sentence your write must meet the test of clarity. The closer the better. Don't let a sentence take your reader away from the highway of your main idea.
Short sentences are almost always better.
Does each sentence you have written belong just where you have placed it within its paragraph. Perhaps it belongs in an adjacent paragraph, perhaps nowhere in the paper. In your first draft of a paper, don't spend time worrying over individual words. But after the first draft is complete, take another look at what you have written. Use words that clarify.