Not all auditions are about being interviewed. After all, the casting director is there to have an idea of your acting skills too. You have to be cast in a movie, remember?
When the casting director hands out the sides* to you and asks you to read for him, that's what we call a cold reading.
Following are 10 points to follow when doing a cold reading, but before that, an essential introductory point is always to be borne in mind:
Don't go for the part. Go for the performance.
1) Go there at least a half-hour before the audition, so you'll have the time to study the sides.
2) On a notebook you always carry with you - as any good actor should do - write down the event of the scene (is it a confrontation, a power struggle, an introduction, an information exchange between the two characters?).
3) On the same notebook, write down your objective**
for that scene (to test/to support/to help/to seek help/to seduce/to impress/to connect/to reassure/etc.).
It is important for the objective not to be a physical one ("to smack him on the noggin". A physical objective is easy to achieve: just go and smack your reader on the noggin).
You have to be very clear about your objective, moreover it has to be simple and straightforward (one word, or a very short phrase at most) for it not to be confusing.
4) Think in terms of what your character wants, don't think in terms of state (cold, angry, disappointed, etc.); it won't lead you anywhere.
5) Choose an objective that showcases your qualities.
6) The audition has to be true. It has to be a dynamic performance, and the performance has to be good, even if you do it wrong: after all, at this stage you cannot know what is wrong and what is right. You have no idea what the casting director wants from you.
7) It doesn't matter if your reader is not good. Take what you get: if they do something wrong and that creates an emotional reaction in you - no matter if a good or a bad one - use that reaction because it represents the truth of the moment.
8) Remember to have an arc*** to the scene.
This means that there must be a beginning, a middle, and an end. In other words, the character must have come to a conclusion at the end of the scene.
9) Connect with your scene partner. They want to see your eyes, so don't keep your face down on the paper.
A good method is:
a- Look at your scene partner while he's saying his lines and react to what he says.
b- Then take your time, quickly steal a look at your lines, and again reconnect with your partner while saying your lines. It's okay to slow down the pace a bit. Besides, your head down doesn't look good on camera.
10) Don't tell the casting director or anybody else your objective, unless you are specifically asked, that is.
Would Houdini reveal the tricks behind his magic? No!
As I said, don't try to do things right. You still don't know what is right and what is wrong: you know nothing about the script, about your character, or about the context. After the first cold reading, the director or the casting director will give you specific instructions. They will tell you what to change or what to leave. But they need something to hang on to in order to do so.
A last piece of advice: have fun and never, ever play safe!****
* The sides is a scene from the script specifically used for cold readings.
** The point of having an objective is also to be conscious of what you are doing. If you are called back, they expect you to do exactly what you did in the first audition.
*** An arc to the scene also means more give and take with the reader.
**** Most of these tips come from my Lee Strasberg Institute audition class notes.