A sure way of controlling those jitters is to take advantage of the space provided and putting your entire body into the presentation. Remember your audience wants you to succeed. They came to hear your message and to learn something they can put to good use. Preparation and rehearsal are just as important for a question and answer session. When we don't know the answer to a question that is asked, we must be truthful and tell them we don't know.
Preparation builds confidence.
Knowledge builds power that keeps you in control. There will be moments, prior to your presentation, when you may feel like excusing yourself from the room and head directly to the nearest closet. Instead, take slow deep breaths to calm your nerves and imagine the standing ovation at the end of your presentation. You may want to consider avoiding coffee. Caffeine and your nervous energy will have you dancing on top of the podium.