what is the best way to get over your stage fright?

I had always been terrified of being on stage. So I did the unimaginable. I was dared to do a standup comedy routine in front of 200 people at a big club downtown Chicago. I killed for some reason. The next time I went down in flames. That made me terrified for a long time. Then I took some classes at Second City with a couple friends. It was excruciating in the weekly shows we did for ETC. After awhile after I'd done close to 200 shows around Illinois and neighboring states it got to be no big deal. So the best way to get over stage fright is to get up on stage until it's just like talking to friends in your living room. In fact, that was exactly the advice I got from another comic, Steve Segren many years ago. And his persona on stage is pretty much exactly like that. It's like you're listening to a pal in your living room.

Do check the other answers as Jared suggests. If you are in a play when you are overcome with stage fright talk to your director who might have experienced something similar and who is there to help you. Other members of the cast are also a good source of support. Discuss the problem with them. Again, we have all experienced stage fright at one time or another and while it can be paralyzing it is rarely fatal. Eventually you will have to deal with this problem yourself. Be prepared for your role. Stay focused on the job at hand. Stay positive about your ability to handle the situation. Remember to breathe! Everyone is on your side, rooting for your success. And then.....dive in, no matter how you feel. With experience, which is sometimes hard won, you will learn how to deal with these feelings of panic. If you are a solo performer ask your friends to help you to understand your situation.

Toastmasters is a great program: https://www.toastmasters.org/

There are some REALLY good answers to this question over here at this other CareerVillage question Do you ever get nervous getting ready to perform and if so, what helps to calm the nerves? I would suggest you check those out to read the answers to your question. Good luck with the stage fright!