Vibrato Technique

1. Open the back of your throat. You can do this by yawning. Try to keep that feeling in your mouth while you sing.
2. Relax your muscles completely. This is important! If you are not relaxed, you will not get a vibrato.
3. Sing with your diaphragm. Breath correctly! Your shoulders should not go up. If you need to, ask ask a friend or your music teacher if you are doing it correctly.
4. You should get a vibrato if you are singing properly, and in the right style. Don't be discouraged if you don't! Not everyone gets one quickly.
5. Here is an exercise from "http://www.become-a-singing-master.com/singing-vibrato.html" to help you: Place your hands at the bottom of your chest and feel where your ribs come together in the middle. Now move your hands slightly below this point. (it's the soft area a few centermeters above your belly button) Now sing a note on one pitch in your easy range. Any note will do. As you're singing this note, push in gently with your hands. The key is to push in, then pull out, and push in, then pull out and so on. Try doing this at a rate of around 3 to 4 cycles a second.
6. Continue to practice! You will be able to sing with vibrato eventually!

Source: wikihow

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