In Google+, Circles has made it very easy to categories your friend list, you can make different Circles with kind of friend group, this is a guide how to use and optimize your Circles.
If you don't invitation to join Google+, Get one here.
Following is the Circles screen:
There are some pre-made circles (ex: Friends, Family, Acquaintances.. etc), Click on Find and Invite tab, Find your friends and family and add them to your Circles. Just Drag that person from above to your Circle, and the person will be added to your group, you can add same person to different circles also. But what is the benefit of adding a single person to multiple Circles? Well, I will explain it with a example, like if you always want to share something with your friends and one person in your office circle, so you can also add him your friends Circle, so you will not have to mention his name while you post something on stream.
Now what if you have to create a new Circle? It is as easy as it was to add people to Circles. Simply Drag the person to the white circle which is on the extreme left side of all Circles, when done, click on 'Create Circle' as illustrated below
Now you have learned how to create and add people to your circles.
Now lets come to, How to manage your Circles.
If you had dropped someone, the in wrong Circle. Then mouse over on the Circle in which you have dropped the person, it will show you all people in the circle, drag the wrong person out o the Circle, and put him in the Circle where that person should be.
How to delete a Circle?
Click on the Circle you wish to delete and it will show you options for edit. Click 'Delete this Circle' and the Circle will be deleted.