If you once forfeit the confidence of your fellow citizens, you can never regain their respect and esteem. It is true that you may fool all of the people sometimes; you can even fool some of the people all of the time, but you can’t fool all the people all the time. - Abraham Lincoln
An effective public speaker should be able to use devices that can capture the audience’s attention. Getting them to go on stage is one effective means for them to give you that much-needed interest. Make them take part. When someone is on stage and happens to be a member of the audience, the rest will always stay attentive. Why? Because they would like to see what you will be doing to one of them. Also, because they think they could be up there themselves, they at least need to know what is going on to save their precious egos from embarrassment.
No matter how good or excellent you are as a presenter or public speaker, nothing beats the excitement of getting someone on stage who really should not be there in the first place. What is going through their minds at that moment when you pull an unsuspecting someone from their complacency is that, oh my gosh, what if the speaker selects me to go up there next? What am I going to do? Then later, I need to pay attention to this. A little bit later, as you go through your presentation, the audience will think, what point are they making? And then, as you take your issue across, the audience will get to think, Now I get it. Because you made them pay attention, you have forced them to listen and respond to your statement in the privacy of their minds.
However, timid and overly sensitive audience members might withdraw from going through the rest of your presentation if they hear you will be calling on them up on the stage. The aim is to gain an audience and not lose any of them.
Make it clear before your ask someone to come up on stage with you that you are asking for a volunteer and that no one will be forced if they do not want to. Notice that if most of your audience is shy, once you finally get someone to be on stage, they will always heave a sigh of relief that you would feel a breeze pass you by.
Another way to get the audience to take part and pay attention is by giving them recognition. Try to acknowledge a single audience member for a specific achievement or a moment of superior performance, or also acknowledge a group of the audience.