Stage presence for auditions and castings for voice
I have a lot of experience in try-outs and castings for voice, both as a competitor as well as a judge. Remember that a good teacher needs to take care also of this aspect of an artist. Be wary of someone who has never thought about it, because maybe they do not have experience and are not interested in your success.
Here is some advice that is often overlooked:
Even the eye wants to play its part
Try to present yourself with clothing and a look suitable for the objective, as well as the song selected. My method of teaching takes into consideration also the coordination between the movement of the body, the aspect of choreography, and the attire for the presentation. A serious professional doesn't leave anything to chance!
Give up your freedom to chose!
If you are allowed to in the audition, it is always better to propose at least two songs amongst which the judges can choose. You will obtain the double effect of capturing their attention and making them understand that you are very prepared. But be careful to not seem overly presumptuous, first ask advice from your voice teacher!
Nice song... who wrote it?
You must always know everything about the songs including who has sung it, who wrote it, in what year and in what album it can be found. It is always good to give an impression of taking your work seriously. In time you will learn to know all of the artistic details that they care about.
Learn the lyrics quickly
Each person has their own method for memorizing the words of a song, a bit like as if it was poetry or nursery rhyme. But a singer must have a method well suited to his or her work. Before even the order of the words one must be able to understand their significance and meaning so that during the song they can freely emerge. If you learn the words automatically you will sing like a robot, but if you learn them with emotion you will interpret them. Obviously never do an audition or casting without the text!
Songs to avoid
It is always better to avoid bringing songs that are part of lives of your selection committee, at least unless they are specifically requested, so that you are not penalized from their deep knowledge of the material. Also avoid singing the most famous songs by an artist that they like, and instead try rather to find those that are more niche that only those who love a certain genre know.
If the try-out is for a musical you will also learn a bit of choreography so that at the very least it is better than a static position.