Perhaps you have been assigned a comparative essay in class, or need to write a comprehensive comparative report for work. In order to write a stellar comparative essay, you have to start off by picking two subjects that have enough similarities and differences to be compared in a meaningful way, such as two sports teams or two systems of government. Once you have that, then you have to find at least two or three points of comparison and use research, facts, and well-organized paragraphs to impress and captivate your readers. Writing the comparative essay is an important skill that you will use many times throughout your scholastic career.
Briefly state your position, state why the problem you are working on is important, and indicate the important questions that need to be answered; this is your "Introduction." Push quickly through this draft--don't worry about spelling, don't search for exactly the right word, don't hassle yourself with grammar, don't worry overmuch about sequence--that's why this is called a "rough draft." Deal with these during your revisions. The point of a rough draft is to get your ideas on paper. Once they are there, you can deal with the superficial (though very important) problems.