Volleyball Setters question. Please Help?

Hey guys I am going to be a Junior in high school and I play varsity volleyball. This year I want to try and be the starting setter. I know I am a really good setter, good bumper, and aggressive. My serve is also probably one of the best parts of my game. But I have one problem, I am a quiet person. I know setters have to be really vocal and I try to be but I just get embarrassed of what people will think of me if I start yelling. If you guys have any tips on how to be more vocal and how to be more confident please help!!!!!! 10 points for best answer!