Some of the best speakers I know employ a tried-and-true technique for Warming up an audience: getting them to offer Applause, three times, early in the session. For example, I recall someone effectively using this approach:

"Let's give a hand for the food service people who prepared and delivered our breakfast this morning. Also let’s recognize the people at (organization) who flew me in to be here with you. How about a round of applause for them? Last, and certainly not least, how about yourselves? You took time out of your busy schedules to be here. Let’s have a round of applause for everyone here."

At this point, what audience wouldn’t be focused, ready to listen, applaud, and have a good time?