At the end of your presentation you say, “Does anyone have any questions?” And no one does. What do you do? You could try waiting for 20 seconds or so and then say, “Well, one question people often ask is…” Come up with your own question to show people what kinds of questions you expect.
NOTE: The question you come up with should be an easy one so people will get the idea that they don’t have to ask something very complicated or difficult.
If the presentation is longer than an hour, it is beneficial to allow questions at regular intervals. This is because the longer people are sat in silence, the less interest they will show in whatever is at hand.
However, most presentations will be shorter than that, and it is advisable to hold off questions until the end. If you have an hour in total for the presentation, you should look to wind down at the 45-minute mark and take questions in the last fifteen minutes.
This will allow you to answer questions and look for feedback on those answers. An open question-and-answer session will enliven matters with more group participation. It will give everyone a chance to participate – in a way which will reinforce what they hopefully have learned.