The discovery draft is your very first effort at writing the paper. The purpose is, as the name implies, to discover what you have to say about your topic at this point.
Randolph Cauthen, Associate Professor of English and Poet in Residence at California State University, Dominguez Hills, describes a discovery draft this way:
A discovery draft is a strategy for coming up with or developing your ideas. A discovery draft is similar to freewriting in that you can write freely, ignoring the structure and the full development of your ideas for the time being. You can also forget about matters of grammar and style.
But writing a discovery draft is different from freewriting in that a discovery draft makes a conscious attempt to focus on and to develop an idea or cluster of ideas. In other words, a discovery draft is like freewriting with an agenda. Because you have an agenda, discovery drafts tend to be more structured than freewritings.
The discovery draft provides a good starting point for the actual writing of your paper, but it is not really written for an actual audience. In fact, what you “discover” about your project may be a number of problems that you have to work through. You may find that your project is still too broadly or vaguely defined. At the same time, you may find that you have more to say about some specific part of your project. Maybe that’s the area to focus on! You may struggle with how to phrase your ideas, or start using some of the keywords and phrases you uncovered in your presearch. Believe it or not, these are good things! Talking with your professor (or you and your writing associate) about these problems can be extraordinarily helpful and constructive!
TIP: Do not try to write a formal introduction or conclusion for this draft. Instead, try to get immediately to the main point of your project and write from there.
I recommend that a good discovery draft be at least three pages (typed, double-spaced). While it is true that grammar and structure are not that important, it would be helpful if you “cleaned up” the paper to make it readable. You should however, be as careful as possible to document the sources of your information. Doing that now will make your job much easier as you continue to write!