Here are some audition tips you may find helpful! I created this video last year, before The SpongeBob Musical: Youth Edition.
One thing I forgot to mention in the video: It's okay to be nervous for an audition -- I still get nervous when I audition for shows! Do your best to remain calm and confident.
Additionally, eye contact with the director is preferred during your introduction/slate. When you start singing/acting/dancing, that's when you want to look behind or next to the director.