1. You will read the play many times and you will see/hear something new every single time you read it.
You know the play really well at the first read-through if you've done due diligence. This allows you to go into that first read-through with confidence. Take the time during the read-through to discuss the story afterward. Ask basic questions, then talk it out. There's nothing wrong with table work mid-rehearsal schedule, either. Returning to the book can be very helpful and throw up new insights. I was consistently surprised throughout the process about what fresh thoughts/ideas appeared during rehearsals and even in performances.
2. Not everyone is going to like you, agree with your vision, or your process for directing. This is ok.
You can't please everyone, and shouldn't. If you worry about this, you will fail. You have a responsibility as a director to stage a play well, and you have the authority to make it happen. Not everyone is going to agree with how you do it, or with all of your decisions. Allow for grexing. It's not about you anyway, it's about serving the play and serving the playwright, the audience, and the actors. You don't need to be everyone's friend. What a relief. On the flipside, don't be a jerk, either. Just because you're the director doesn't mean you get to swell with power and be all, well, jerksome.
3. Casting is important.
Holy smokes is this important. It is fine to hold extra auditions and callbacks. Get it right. Ask questions, do a little research on those who audition. Has he or she played roles like this before? If not, what interests them in the role and the play? Take your time and get it right. There is no decision you will make that is more important than this one.
4. Directing is a lot like teaching.
Every actor has a different style, a unique process toward finding their character, understanding the story of the play, learning blocking. Some respond well to written notes, some work better with spoken notes. Some need extra encouragement. Some need to move as they say their lines in order to learn them. Work with their different learning styles. This is not extra work for you. It's a bonus, really. I gave notes two ways. After rehearsals actors were handed notes that were written on index cards, and I also spoke directly to the actors. Visual and auditory.
5. Rehearsals need structure and discipline.
This is like teaching, too. An unruly class leads to little getting accomplished and a frustrated teacher. Begin on time and end on time. Don't allow people to be habitually late. It's a waste of time and is disrespectful. I began rehearsals with warm-ups. It's asking a lot for someone in community theatre (an unpaid position) to show up at 7 p.m. after a long day at work and expect them to just "get into character" and be ready to go. We started with physical warm ups, then vocal, added more movement, and then we began what was on the rehearsal schedule. Don't keep working when actors are tired, and end rehearsals happily.
6. Be kind to your Stage Manager. Praise her often. Be kind to the Technical Director. Praise him often. Include the crew.
Your SM is there for you during rehearsals, she answers questions about props from actors, takes phone calls about rehearsal schedules, she deciphers your written notes to actors, makes sure that everything is in the proper place during later rehearsals and performances. She will know the text of the play like you do, and will keep track of your blocking choices. My SM was like an angel, and I hope I reminded her enough of how helpful and wonderful she was. My TD helped me to overcome my fear of ladders, orchestrated the crew in the construction of the set, and turned the house into a home. I did my best to include the crew in the creative process, and asked their advice on things where they had the knowledge base I lack.
7. Say yes or no. Avoid maybe.
You have a vision. Stick to it. Actors do not want to hear, "Well, maybe this will change." Or a "Maybe ..." from the director when they ask a question about whether or not what they are doing looks right. It either does, or doesn't, is or isn't. Shit or get off the pot, as my father used to say.
8. Praise actors early and often, and listen to them.
Rather than saying "Your entrance was good at the beginning of the scene, but you need to be a little slower." Say, "Your entrance was good at the beginning of the scene, and it really looks terrific when you move slower." In very early rehearsals I gave little direction and just watched and took notes. Most of what came naturally to them worked. As they got comfortable with their characters and their lines were learned, there was lots of room for them to play and improvise. Some of it worked magically and I said so. Some of it didn't, and we tweaked. When an actor says "This blocking doesn't feel right," I listened and asked questions like "What do you think will work better?" Often they knew what worked. If not, we worked on it together. I know this isn't how every director works. Theatre is a collaborative process. I don't have all the answers.
9. Don't apologize when you don't have to.
Sure, admit when you're wrong, but when you're not, don't apologize. The older I get, the less I appreciate self-deprecating, sort-of-humorous apologizing. It rots confidence in yourself, and in everyone around you. Everyone makes mistakes. Learn from your mistakes, laugh them off when appropriate, and move on.
10. Challenges are learning experiences.
Has something not quite worked out the way you thought it would? Good. What can you make from the pieces? What did you learn? My biggest challenge was the first tech rehearsal. I had no idea how much cacophony would happen the night the lighting and sound technicians arrived. More instruments in the symphony!
11. You can't control everything, and you shouldn't.
Sometimes the most incredible moments are the ones that aren't orchestrated. In the end, when you're sitting in the dark in the back of the house, and the audience is completely engaged in the story, you have zero control over what happens. It's up to the actors and the crew. If you've done your job, it's beautiful.