9 Lessons Learned from 15 Years of IT Project Management

1. No one except PMs care how something gets done as long as it does.
Don't try to make people change to accommodate whatever complex, overly sophisticated PM process you think makes the most sense. You'll just piss them and they won't do it. It sucks but email / IM / face-to-face is what works. 

2. Choices, choices, choices...
Always give people options. Just make damn sure they all are choices you are OK with.

3. Respect the Zone.
When you bug developers always politely ask for the to give you a moment when they reach a good break point. It can take up to 20 minutes for a developer to get into the zone. Interrupting this process kills their productivity and makes you look like a jerk.

4. Under-promise and over-deliver.
Within reason. Just don't sandbag people.  

5. Estimating is a black art.
Take estimates that don't include ranges or confidence levels with a very large grain of salt. 

6. Give credit where credit is due.
You'd be surprised how many organizations are bad at recognizing good work. A heartfelt public thanks can be worth a lot to your team.

7. Don't panic.
Especially in front of your team. Ever. Do your best to shield them from the insanity above and below you. They will recognize and appreciate the effort.

8. Never take it personally. 
No matter how much it seems it isn't about you. Remember most people want to help but are busy fighting their own battles. Analyze the situation dispassionately and weigh your options carefully.

9. Without trust and at least some goodwill your project will fail.
Once earned work as hard as possible to preserve both.