Understand their requirements:
First thing you should do is to read the advertisement carefully. You must understand what type of character they are looking for and what are their directions regarding age, gender, looks etc. Sometimes, those auditioning also give instructions which can help you in picking the right monologue.
Know your character:
You should do some research about the character. Knowing its psyche can really help you select appropriate dialogues. For example, if you are playing a role of a tragic hero then you will go for dialogues that are deep, gloomy and wise.
It is always better to choose an emotional monologue as it gives you an opportunity to display strong emotional side of yours. Remember, most of the characters in theatre are emotion-based so you must find a monologue that gives the impression that you understand the character.
Look for a neutral monologue:
You should go for a monologue that makes sense even when it is out of the context of the entire script. Do not choose complex and confusing monologues rather you should pick one that does not require explanation of a story line.
Though, you can pick monologues from films and dramas but it is better to choose those which are written especially for theatre. For example, you can pick a few powerful lines from Shakespeare’s “Othello” or “Romeo and Juliet”. If you are not comfortable with the Victorian language then you should pick a monologue from modern dramas.
Show your versatility:
Do not look for ease rather you should challenge yourself by picking a monologue that can prove you are a versatile actor. Moreover, you should not depend on just one monologue as the judges can also ask you for more. Be ready for anything and stay confident throughout your audition.