- you may want to wait on videotaping performances until the first callback. There is no point in videotaping people that you know at first impression will not make the cut. It just wastes time.
- SAG actors require sign in sheets. SAG recently lowered their rates to 100/day for low budget features (under 200k) and fully deferred for low budget short films. So SAG is almost always an option now.
- don't read an opposing part with the actor, you won't be able to concentrate on the actor. It's okay to use PA's/coordinators for reads in my opinion. Bunch together different actors and have them play different parts
- swap actor's parts just to change things up, an actor may do better in a different role
- I avoid open calls whenever possible, except for casting extras (where anything goes including getting people off the street

) For lead roles I always go by references from other filmmakers, producers, theatre directors, etc. The closest I'll get to an open call is posting a bulletin for all actors to mail in headshots/resumes to an address.
- give all actors as much respect as possible, as you may want to call them later as extras, or for minor parts
- by the same token never give an actor a part - (or the impression that the actor has the part locked up) until you have done callbacks and you are sure you will not see anyone else.
- give them water
- schedule them at 4 per hour or at most 6 per hour. Otherwise you seriously won't have enough time.. and/or all the actors will be waiting for hours, and word will get around, possibly preventing the better actors from showing up.