Make it Messy
It may sound counter-intuitive. You're a smart actor: you prepare tirelessly for your auditions, breaking down every beat and digging through the script for clues, answering all the questions for yourself so you are undeniably prepared.
Good job! Work and preparation are crucial for auditioning. However, the key is to make sure your audition isn't overly polished, too perfect.
There's a delicate balance between preparing and over-preparing. Remember, too much practice makes your choices permanent and the goal is to leave yourself free to play and make discoveries in the room.
Think about a performance that moved you, be it in a film, on TV, or on stage. My guess is it was raw, real and a little bit messy - just like real life. For casting directors, the most compelling auditions are those that feel like the actors are making up their lines on the spot.
The key is to do your work, prepare, break down the script, and then find the freedom within your preparation to take risks. Make strong choices, and be ok with messing up.
In life, we rarely prepare how a conversation will go. Mimic real life. Really listen to the reader and challenge yourself to react in real time. Trust that your good work and preparation will carry you and free yourself up to be messy.