I laugh a lot. Se funny videos and distract myself. The best thing I do is that I even meditate like Chant OM in my mind in calm myself down. You can even talk to someone it may help.
I think it natural and necessary, make you realise you are about to do something. Just try to take it easy on you and let it not reflect on your face and body. You only feel relaxed when it pass.
I think it is natural and necessary, makes you realise you are about to do something big and changing. You will feel relaxed when it pass, until then breathing, faking a smile and confident body posture is all you can do. Tbh!
When you have to attend a big event, anxiety comes naturally to you. So the person should focus more on keeping herself/himself calm. And thinking positive is the best key.