How to use Circles in Google+
As you start playing with Google+ and Circles, here are a few guidelines for different tastes.
- Simplify your Google+ experience in three easy steps
Volker Weber's simple guide for starters. This is the way I do it so far. - Google+, A Collaborative Document: Creative ways to use Circles
Not a cohesive approach to manage your circles, rather some specific usage patterns you can add. - Google Plus - One50, Two50 and TheRest
Luis Suarez' personal approach to keep it simple with lots of connections. And lots of other good info here. - Managing your Social Graph with Google+
Christopher Allen's highly sophisticated approach with numbering and everything.
If you want to understand Circles and some of the not so obvious implications, these are good reads:

