One thing that directors like Ron Howard have going for them is the experience that they've had in front of the camera prior to going behind the camera. The advantage of having been an actor before trying to direct other actors has to provide a great deal of insight.
If you're a first-time director and you don't have that kind of experience, however, all is not lost. In fact, even if you have a film or two under your belt, you're bound to find some insight in this article on working with actors.
"The way that you talk to your actors during this process is massively important. You have to give them clear, useful feedback. If you get it wrong you can make things worse rather than better. The first tip is that regardless of how bad a run through is, you've got to find something positive to say; even if it's only " I really like the way you made eye contact during that run through … however," and then you talk to them the stuff that didn't work, but again don't be critical, use phrases like "I wasn't completely convinced by the way you entered the room, how did it feel to you?" Usually the actor will respond by admitting they don't really understand what the character is doing at that point and you can give them some back story, which will help the actor try something different."
filmmaking.net: Working with Actors for Film
