The proper format for an essay outline is an alphanumeric system using Roman numerals, capital letters, Arabic numerals and lowercase letters. The purpose of such an outline is to break down the parts of the essay in a hierarchical manner.
A proper outline starts with the title of the essay at the top. Next comes Roman numeral one with the word "Introduction." On the next line, the writer indents and places a capital A followed by the thesis statement. The thesis statement is a single sentence relaying the purpose or position of the essay. The final line for the introduction is the letter B briefly covering the main points of the essay.
Writers outline the first body paragraph under Roman numeral two. Next to the Roman numeral goes the first main point. Capital A is indented and indicates the first support for the point. After another indent come Arabic numerals for details related to that support. If necessary, the outline goes into further detailing with indented lowercase letters under the numbers.
The format for each subsequent body paragraph follows the above pattern. In general, each body paragraph should include roughly the same amount of outlined information.
The conclusion comes at the very end under its own Roman numeral. The format is similar to the introduction in that it includes the thesis statement. However, the conclusion often includes a summary or some final thoughts, which the writer maps in the outline.