Although the OP started the thread back in October and has surely cast and completed his or her school project by now (hey Bmore Brecka, how'd it go?), if anyone else is looking for tips, this is what I do:
Make sure I have a sign-in sheet for them to fill out contact info AND indicate their availability for the days I will be shooting. Very important!
Give them sides (a few pages of the script) before the audition, so they can read it and let some ideas percolate before actually coming in and reading cold for me.
If possible, choose scenes for them to read which are important to you, and which involve interactions with other characters and a rise and fall of emotions.
Have several copies made of the sides, because someone always accidentally takes one home.
Have another actor there for the day (or a few actors who can only do half-days, or whatever they can swing) to read the scene with them to see how they interact with other actors. Of course, I buy lunch for the actors helping me out, and give them some money and cabfare or a Metrocard (subway). If it's someone who is already cast in a role in my project, I may ask their opinions on the actors coming in, too, because they might get a sense of what it would be like to work with them.
Have them read it several different ways, each time making different suggestions on how to approach it - this gives me an idea of how well they listen, follow directions, and how imaginative they are.
Have someone with me for a second opinion, to get lunch, and to help me keep everybody's headshots and my notes organized.
Of course, my gut instincts are usually right, but these are a few ways that let me assess if I want to work with someone and make the process easier.
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