If you get nervous, you can use an Aikido technique I discovered. Lean on the left side of your body and it will engage your right brain, which is your creative side. You cannot be judgmental when you are right brain thinking. Left brain thinking is critical, judgmental and logical. The “what if” scenario is generated from the left brain.
Another Aikido technique when you need a burst of energy is to apply pressure with your fingernail at the tip of your thumb. It sends energy to your brain. One other method is to take three deep belly breaths. Hold the breath in your stomach for a count of three then slowly blow out the air through your mouth.
When I first started speaking I would stand up in front of the room and not move one inch from where I began. It took an entire year before I was comfortable enough to move about six inches in either direction. Then I spent another year to learn how to use my hands and arms with any accuracy.