What are good exercises to develop vibrato?

Question:

What are good exercises to develop vibrato?

I want to perform "Somebody To Love" by Queen In the spring at my school Talent show, called Austin Idol. I have a good enough voice, not too great, and i can get an ok vibrato on a certain style i can sing in. So i wanted to know if anyone could help me with some tips on how to do improve my vibrato...i dont have money to go to a vocal or singing coach :( ! Please let me know!

Best Answer - Chosen by Asker: The best way to develop vibrato is to sing a note and move it back and forth like a siren, start slow between two notes and continue to get it faster and faster. the only way you'll be able to get it faster and nicer sounding is to practice. But starting your vibrato by doing it over the top is by-far the best way to learn how to sing vibrato! the more extreme an over the top the siren sound, the better! good luck :)