When you present in front of a crowd of any size, your goal is to provide value with your content. Providing value is the broadest definition of presenting that I can think of. Comedians offer laughter. Teachers give education. Mentors provide insight. They all give something worth listening to.
As you prepare for a presentation, remember this. For what other purpose do you exist at the moment you present? Don’t let vanity grab hold and cause you to wonder what people may think of you as a presenter. You should disappear into a presentation as the information and insight you convey to the audience takes over. You should get the audience inside of their heads rather than attract attention to you. Speak with an end in mind and make sure that end is powerful. If nothing else, make sure your audience leaves your presentation with at least one powerful, memorable phrase or idea.