I have been musing on this for a while, and it is perhaps a repetition of things said in the past, but is worth saying again. When I say take risks in your audition, what I actually mean is - allow yourself to actually express yourself - the reason (I believe) anyone does this is singing thing is because at some distant (or not so distant) point in the past, he/she felt a desire to express themselves through the use of the voice. This is a very basic, primordial instinct, and is a completely individual expression. One of the unfortunate side effects of voice lessons, coaching, diction classes, staging classes, etc. is a certain homogenizing of this very unique urge. Of course, that is not the intent of any these things. Rather, they are intended to refine and bring out in the most beautiful way, the voice that is inside (rather like the way a diamond is processed),
It seems to me the most successful auditions and performances I hear are those where training has not blurred the very personal expression and talent of the singer, but rather the opposite - it is enhanced and highlighted.
I think this is an important thing to hold onto as you plan any audition - and performance.