Make a fist with your left hand.
"Freaking out is primarily associated with the left hemisphere of the brain," wrote The Atlantic, so researchers found that making a fist with your left hand helps "draw focus away from the left hemisphere" and turns off the worrying part of your brain.
Cool, right? Will you try it? Do you find public speaking nerve-wracking?
P.S. My elevator phobia.
(Photo of Yves Saint Laurent being pushed onstage, Paris, 1986, via Messy Nessy Chic)