On the left-hand menu, select the page Working Groups. On the page, you will see a collection of the Working Groups already created. Above these on the right-hand side is the button Create New Group. Once you have clicked on the button, as well as being asked to type out a group name and description, you will be asked to choose the privacy level of your group: secret, private, or public. After this stage, you will have to wait for your group to be approved by an administrator.