Everyone hates micromanagers. Then why do we keep running into them? Why are they our bosses? It's like a bad stomach virus. If you are a manager, odds are that you micromanage someone, or some project, or some group. Why do you do that?

One word: INSECURITY.

You are probably insecure about something, someone, or some process that is either uncomfortable or out of your knowledge zone. And because it is, you spend more time than you need on it. Much more time.

How do you let go of that bicycle seat and let that person, project, or team ride off into the sunset? It's easy - you need to feel comfortable, not them. So do this:

If it's a Person - there is probably something about them that you don't trust (because micromanagement comes from not trusting someone). Once you figure that out - let's say it's their attention to detail - work with them on this. Bring it to the forefront and discuss it with them. Give them more and more difficult tasks that stretch their abilities. If they succeed, you can pull back. If they fail, you're there to pick them up (get that? let them fall!).
If it's a Team - there is probably something about you that you don't trust. You need to see a coach and figure that out. Candidly, I've coached a lot of upper management types and when they suffer from micromanaging their team (feedback from a 360 assessment), they usually have deep trust issues (from being severely burnt in the past) and have to slowly reliquish control.

But that's easy. Start with your stars and give up control slowly. You'll see that you will have more time for the more complex parts of your job.

Enjoy the journey!