While figuring out how to sing vibrato can seem complicated, it might be easier than you think. Many will say that singing vibrato is something which will just occur to a healthy singer before long, but this isn't necessarily true.
Singing vibrato is something that is controlled through the singer, along with a good healthy vibrato happens about six oscillations per second, and any slower than that is called tremolo and then any faster than that is known as a shake. You want to avoid too fast of vibrato and not fast enough of vibrato because both sound terrible.
If you have anxiety when walking on stage to do a performance that is often called stage fright. Performers of all types face this prevalent problem. Even to some degree professionals still have a measure of stage fright while being on stage.
And so I wish to give you a few tips about how to avoid stage fright and also the anxiety that comes with it. One of the main things that that you can do to curb stage fright is to be prepared. Preparedness is among the biggest ways to curb stage fright. Being prepared allows much more of a feeling of peace, and peace gets rid of the anxiety and fear that accompanies stage fright.
Comfort and peace are usually a result of being prepared, having practiced for your craft as well as your songs and knowing your lyrics, and with this nervousness will be much less.
The small things also matter like laying out what you are going to wear when you perform. I understand this sounds just a little trivial, but it is a mix of the little things that causes the most anxiety and stress. Anxiety and fear become less and less while you look after all of the little things.
If you have a chance, lots of people find it comforting to visit the venue before performance day. Visiting the venue takes some of the unknowns from the equation, so you tend to be more relaxed and know what to expect when you get there. Taking a visit to the venue you can observe will need to wait on stage, where everybody will be sitting as well as in which you will stand and come to the stage.
People who are afflicted by stage fright often feel a lot more peaceful having visited the venue. Learning harmonies is another common problem for many singers. This is often a difficult thing as it was for me personally for many years. However with some practice and listening and copying others you'll have harmony down.
So keep at it and also best of luck as you learn how to sing harmony.