To create a Group, click on the Address Book button in the top navigation menu:


This will bring you to your Address Book.


You'll see two columns. The left-hand column is for your Groups or lists. The second column is where individual contacts are kept.
Click on the plus symbol at the bottom of the Groups column. A text box will appear for you to enter a name for the group you wish to create.

When you have entered the Group name, press Enter. The group will be created and will be empty.

To add contacts to the Group, simply click-and-drag each contact into the list you want them in.