Make sure you have a planned purpose to your activity. Encourage voluntary contributions, challenge or questions. Group work Group discussions, small team exercises, role-plays, case studies, projects for later presentation. This principle operates not only for the benefit of the student but for the instructor as well. With properly planned participation, you are now free to work with individual learners, observe student groups and prepare yourself for the next session.
Participation is an effective way to get more of the senses involved and increase the learning.
When we discussed Stimulus, we said that words alone are not very effective. We remember more of what we do and say than of what somebody else says or does - because we're involved. Don't use involvement for its own sake but to increase learning. The world of advertising knows well the effect of repeating a message. Stop and think how many times you've seen the same ad on TV or in print.