When I was about 11 or 12 I decided I wanted to be a Broadway actress. I started singing in local competitions, for my school talent shows, almost anywhere I could get my hands on a mic.(I’m only 14 though, so that’s not a lot).
Things to remember though!
1. Seriosuly, right before you go on, think of ANYTHING but the words to your song. You’ll screw up, bad.
2. Calm down. Don’t be nervous that you won’t be liked, blah blah blah. These people are here to see you ;].
3. Enjoy the moment. I’ve never experienced Runner’s High, but I’m willing to bet Performance High is miles higher.
4.Remeber all your proper singing techniques
5. Work on the peice till you have it to a tee, so that you won’t be nervous about forgetting anything.

Good luck!!