One of the most effective tips I have learned after decades in post-secondary teaching and adult education is this: encourage people to applaud for one another. The form of the applause will change depending on the situation, but the effectiveness of applause will be constant across different ages and different circumstances. Applause is contagious.
What happens when people clap? It doesn't take long before they begin to smile. And not long after that, they begin to suspect that there's something worth applauding. This is true whether they offer genuine applause or whether they applaud because the leader tells them it is required. I have watched many different people under the influence of applause. Most of them look embarrassed, at first. They look like they are not sure that the applause is really for them.
And then, after it starts to become clear that applause is non-negotiable, something lovely begins to happen. Although people might still squirm a little, there's a light in their eyes as they do. They begin to stand a little more firmly. Even the quietest begin to feel a little more safety.
And then, the best part of all starts to become clear. When people applaud, they begin to listen. Because they clap, even their ears open and their eyes open, just a little. Because there is applause, there begins to be the possibility of communication.
So if you're running the room, make people applaud.