1) Think you know everything.
If you were just promoted to Production Manager, you may feel you know everything about production. Even if that were true, and it isn't, you sure don't know everything about the most important part of your new job, managing people. Listen to the people around you. Ask for their input when appropriate. Keep an open mind.
2) Show everyone who's in charge.
Trust me, everyone in your group knows who the new manager is. You don't have to make a big show about being "the boss". You do, however, have to demonstrate that, as the boss, you are making a positive difference.
3) Change everything.
Don't re-invent the wheel. Just because the way something is done isn't the way you would do it, it isn't necessarily wrong. Learn the difference between "different" and "wrong".
4) Be afraid to do anything.
Maybe you didn't ask for the promotion. Maybe you are not sure you can do the job. Don't let that keep you from doing the job the best you can. Upper management wouldn't have put you into the job if they didn't have confidence that you could handle it.
5) Don't take time to get to know your people.
Maybe you worked alongside these people for years. That doesn't mean you know them. Learn what makes them excited, how to motivate them, what they fear or worry about. Get to know them as individuals, because that's the only way you can effectively manage them. Your people are what will make or break you in your quest to be a good manager. Give them your attention and time.
6) Don't waste time with your boss.
Since he/she just promoted you, surely he/she understands how busy you are and won't need any of your time, right? Wrong. Your job, just like it was before you became a manager, is to help your boss. Make sure to budget time to meet with him/her to both give information and to receive guidance and training.
7) Don't worry about problems or problem employees.
You can no longer avoid problems or hope they will work themselves out. When something comes up, it is your job to figure out the best solution and get it done. That doesn't mean you can't ask for other's input or assistance, but it does mean you are the person who has to see it gets taken care of.
8) Don't let yourself be human.
Just because you are the boss doesn't mean you can be human, that you can't laugh, or show emotion, or make an occasional mistake.
9) Don't protect your people.
The people in your group will be under pressure from every direction. Other departments may want to blame you for failed interfaces. Your boss may want to dump all the unpleasant jobs on your department. HR may decide the job classifications in your area are overpaid. It's your job to stand up for your people and make sure they are treated as fairly as possible. They will return the loyalty.
10) Avoid responsibility for anything.
Like it or not, as the manager you are responsible for everything that happens in your group, whether you did it, or knew about it, or not. Anything anyone in your group does, or doesn't do, reflects on you. You have to build the communications so there are no surprises, but also be prepared to shoulder the responsibility. It goes hand-in-hand with the authority.