How does the next paragraph end?

How to give a presentation
Focus your presentation.
Having a long, rambling presentation that is hard to follow is not going to win you any audience interest. You need to make sure that your presentation is clear and focused and that any asides you throw into it are there to back up the main point.
It's best to have 1 main thesis statement or overarching theme and 3 main points that back-up or flesh-out your main theme. Any more than that and your audience is going to start losing interest.