Below are 10 singing warm-ups for the voice from Singing Coach, Caroline Selia, that you can use before each audition, callback, or performance. They are listed in the order that you should sing them; however, if you're in a rush, you might consider doing: 

[Yum], [Ged-da], [Mi-Ma Short], [Mi-Ma Long], & [Me-Who]

vocal exercises for maximum vocal effeciency. 

These singing warm ups will change periodically, and more will be added, so keep an eye out for new additions weekly!