Most people speak too softly and the result is often mumbling. Speaking up can also make you feel less nervous. Force the audience to visualize. The listener's mind is hungry for pictures. A friend of mine once told me . . .
Pauses are perhaps the most effective technique for regaining the attention of the audience.
Try it and you'll see all eyes looking back at you for your next statement. Save handouts until after your presentation. If you give people materials at the beginning of your talk, they'll read instead of pay attention to you. This is an issue that touches all of our lives in one way or another. As a pediatrician, I share your commitment and propose to assist you in your outreach efforts.