How To Rid Myself Of Shyness?

My ultimate dream is to be a singer and im working towards that right now. Here's the thing, on thursday i was in dallas to audition for The X-Factor. I didnt make it, and here's why: i was nervous and nerves make my voice clam up and then i cant sing for anyone. so ultimately it was my inexperience that messed me up, so does anyon have any suggestions on how to rid myself of this shyness? American Idol is coming to houston in August, and right now i'm going to do some karaoke to start loosening up in front of people. Any suggestions will help me. Thanks in advance!!!