To get your audience involved in your presentation, ask questions designed to get a verbal response. Choose questions you know the audience is likely to know or have an opinion about. If you are able to get the audience to respond to you verbally, you will be able to keep their attention more focused on your presentation. Alternately, ask questions of the audience and give them a short time to answer the question and discuss the key point with another audience member. This will generate opinions along with additional questions and concerns.
People appreciate a relaxed and spontaneous speaker as much as the speaker appreciates an attentive audience. One way to help both speaker and audience to relax is to interact in some improv-style comedy or drama. Pose questions or situations to the audience, and ask for volunteers to come forward and act out the situations.
Merely asking for audience participation will yield rewards. Ask the audience to repeat a key phrase or statement. Encourage the audience to clap their hands. Walk out into the audience with a microphone and ask specific people for their opinions. The simple act of asking the audience to participate should help them focus and respond.
Just as you can engage an audience by asking them questions, you can also involve an audience by allowing them to ask you questions. Have audience members raise their hands with questions or step forward to a microphone. Alternately, offer paper and pencils and ask the audience to write questions to you that can be turned in during intermission. Read through a dozen or so questions and address them after the break.