I've been in performances since my 5th grade play, yet I still get the same nauseating feeling and rapid heart rate before the curtains open! But I have learned some ways to handle my anxiety and have the right mindset so I can perform to the best of my ability. I hope my 3 tips will give you an idea of how to tackle your stage fright!
Tip #1 - Focus on your breathing. Imagine a calm place, for example, the beach with it's gentle rolling of waves and slight breeze through your hair. Don't take it for granted, this method will definitely slow down your heart rate and clear your mind!
Tip #2 - "Shaking off the nerves" isn't a true statement. Don't dance around and think that will make you more hyped to perform because it will actually increase your heart rate. Instead, stay still and convince your body that there's no reason to get anxious!
Tip #3 - Remember why you want to perform and why the audience has gathered to watch you. You want to show people what you have to offer, and your audience is there to be enlightened! It's as simple as that, so no need to sweat about it!
Comment on some of the tactics you use, I'm sure all of us would appreciate your advice!
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https://www.youtube.com/watch?v=l-5ivq0ntlo