If you are a league, you can add divisions to put your teams into on the Team settings page.  If you are a club and have a paid account, please contact Support for help with setting up divisions.

On the teams settings tab, check the box that says "I need to track standings for groups of teams, such as divisions or conferences". 


Once checked, the divisions tab will appear in your settings list. Add your divisions, one per line. 


When you have divisions, you can assign teams to divisions on the teams page using the dropdown menus.