Excellent article on stage fright and what you can do about it. The author, Mikael Cho, talks about how adrenaline and the fight-or-flight syndrome get in the way when we’re getting ready for a presentation (or even a difficult conversation).
I teach a class on adrenaline flooding, using material from Conflict Unraveled (I’m a certified instructor).
Along with Cho’s suggestion of slow breathing, I’d recommend adding some strong large-muscle movement to help disperse adrenaline. Climb a few flights of stairs, for example, or lean against a wall and use your legs to push forcefully against it.
And don’t forget the best way to put yourself at ease: practice! As Cho says,
We’ve all heard the saying, “practice makes perfect.” The main benefit of practice is to increase your familiarity of a given task. As this familiarity increases, feelings of anxiety decrease, and have less of a negative impact on performance. In other words, the more comfortable you are with your presentation, the anxiety you feel about speaking in public.
I’d add: when actors rehearse, they use the time to explore the possibilities of a scene, not to repeat it mindlessly. So even in practice, keep coming to the task as if for the first time. Discover unexpected meanings and new ways of expressing your ideas. Then you’ll be ready for surprises when it’s time to do it for real.