When creating your league table, you do not have to add your own team to the list. This will automatically be accounted for when the league table is created.
However, should you wish to edit the list of teams in your league, you can do this via the 'Create/Edit League" section' - which is accessed from the dashboard area.
To edit your teams, click Add teams (create fixtures) in Manage menu (right)
The Add teams (create fixtures) pop-up box (below), will allow you to edit the list of teams which appear in your league table.