In Chicago you will find that there are several types of auditions that you can go to, casting auditions that you will typically see listed are the agented audition, the basic audition, the musical/dance audition and the infamous cattle call. They all have some common factors in Chicago like you need to introduce yourself and make sure you thank the directors and or producers after the audition without being really invasive or bothering about it of course. Usually a simple thank you for your time will suffice. And make sure you are being extra with your introduction. Keep things simple and to the point.