Once a topic has been chosen, ideas have been generated through brainstorming and free writing, and a working thesis has been created, the last step a writer can perform in the prewriting stage is creating an outline. An outline allows a writer to categorize the main points, to organize the paragraphs into an order that makes sense, and to make sure that each paragraph/idea can be fully developed. Essentially, an outline helps prevent a writer from getting stuck when performing the actual writing of the essay.
An outline provides a map of where to go with the essay. A well-developed outline will show what the thesis of the essay is, what the main idea of each body paragraph is, and the evidence/support that will be offered in each paragraph to substantiate the main points.