Help!!How can I take down my nerves??

I have solo and ensamble contest tomorrow and I am taking a Solo. I am more nervous then i have ever been in my life. This will be my second solo ever. The first solo I ever took,I was just getting over a cold and when I went to take a breath a ton of goop got all up in my throat and I have to start over. Does anyone know any ways to take down nerves? Any help would be forever appriated!! Thank You!!!