Start with an introduction. In the outline, the introduction can be limited to one sentence: the thesis of your review. The thesis is, in essence, the main idea of the review, the point you are trying to establish in your text. Label this section "Section 1" or simply "1."
Outline the first section of the essay. Start with a major idea that reinforces your thesis statement, and write it down. Because it is just an outline, you can write in full, proper prose form or in shorthand. Label this section "2."
Develop one or more supporting points or details that provide evidence for this idea. List the details underneath and label them "a," "b," "c," and so on.
Establish the next main idea that you will discuss in your review. Label it "3" and align it with sections 1 and 2.
Develop supporting details (again, labeled "a," "b," "c," and the like) as you did for the previous section.
Continue in this fashion until you have outlined all your ideas and corresponding support details in connection with your thesis.
Finish the outline with a concluding section, labeled with the corresponding number (which depends, of course, on how many previous sections you have added.) In the outline, limit the concluding section to one or two sentences to provide a gist of how you will summarize and wrap up the literature review.