The outline plays a subtle but important role in the message. It is the roadmap that you will use to explain, prove, or apply the proposition to your audience. It should be clear, logical, and memorable but should not draw too much attention to itself. The outline consists of main points and sub-points. The purpose of the main points is to explain, prove, or apply the assertion made in the proposition. The purpose of the sub-points is to explain, prove, or apply the assertion made by each main point.