I remember my choir teacher in high school told me, 'When in doubt, sing loud.' I'm a terrible singer, but I always auditioned for the musicals, and would get cast in them because I really would just put it all out there. That was really good advice, and I think it works for everything, not just acting.
I have such happy memories of performing in a choir and I don't think I'd have got where I am today without all that experience. So my advice to young singers is to either join your school or church's choir or find one in your local area. Choral music at any level teaches you so much about musicianship and blending your voice.
My grandmother took me to church on Sunday all day long, every Sunday into the night. Then Monday evening was the missionary meeting. Tuesday evening was usher board meeting. Wednesday evening was prayer meeting. Thursday evening was visit the sick. Friday evening was choir practice. I mean, and at all those gatherings, we sang.