Don't think you need to do everything yourself.
I know, I know, I know. If you want something done right, do it yourself. Right? Sure, if you're doing ONE thing. If you think nobody else can do it (whatever) right, you have a problem. If you have a limited budget or are stretching what you do have, think about which key people you really need to pay depending upon what aspects of the film need the most attention (art direction, sound, continuity, etc.)
Noob filmmakers and directors all seem to have the same delusion that they need to oversee every single aspect of production. This is unfortunate and a major mistake since it really takes away from what the director should be doing (directing) and if you are a beginner in the craft of directing/filmmaking, that's not good.
Know what you absolutely need.
When you head into battle on shoot days and people are dropping balls and the shit is hitting the fan, you really need to know, beyond the shadow of a doubt, what you need to get out of your actors to make the story work. Feature length films are always a mess in terms of intention vs. reality.
When your practical effects take 3 times longer to set up and then they still don't work, then what?
When your lead actor was out drinking all night and can't remember his lines, then what?
When you get hammered by an unexpected storm of biblical proportions, then what?
Plan B, that's what. Always have a Plan B which is merely a minimalist approach that allows you to have the shots for the scene for the film that will work on an acceptable level. The key thing is getting the film finished, so be ultra aware that the ever present beasty called compromise will be nipping at your heals every single day. Be ready for it or you lose.
Be a great communicator.
Sounds simple, doesn't it? It's not. Part of the gig is to understand how to communicate your expectations to other people. Especially the actors. As a director, you need to be able to interface with your production staff, (generally only the key crew) and your actors. You, as the director have the film in your head. You've already seen the film - in your head.
When execution time comes, you need to extract what's in your head and format it for the fine folks who will execute the production of the film, or all will be lost. If your key crew need to keep asking you what you want and how you want it (or worse, have to guess), you are in trouble because you are not only wasting time, but there's an obvious gap in communications that could lead to the old compromise monster eating your film.
It's uber importante to sit down with your keys and go over each and every scene in the script to address all aspects of shooting the scenes, well before principal photography starts.
While on the set during shoot days, you have to speak in such a way that the people you're speaking to (actors & crew) can understand you the first time and need minimal clarification OR you will waste time and will become burned out.
Make sure you have some consistency when speaking about characters on set (to your DP, sound mixer, wardrobe, etc.) Use NAMES, not "the guy" or "the girl." Be very direct, illustrative, and don't waste time. Be very, very clear with your key staff and key crew and try to make sure they understand what you are telling them at all times and above all, do not make your key people guess at what you want, ever.
©2009 Chris Santucci