An outline is a snapshot of the major sections/topics/arguments you will be covering in your thesis paper. A good pointer to keep in mind is that your headings and subheadings from your outline will eventually become your Table of Contents in your thesis paper!
Outlines can be formatted in different ways. The key is to choose a format that is most useful for you, or one that makes the most sense to you, in terms of organizing your thoughts and research.
Outlines are typically formatted using a combination of roman numerals, upper and lower case letters, and numbers.

Make an outline in the format of the link I attached from Purdue owl on an argument for gun rights because they are our god given right. The outline should CLEARLY HAVE ARGUMENTS AND SUPPORT FOR OWNING A GUN.