This step will explain how to create/manage new segments to the expanding menu.
From the admin panel, find Design -> Menu Items Management
Click Actions next to Header to access Submenus
From the Titles menu, select the menu segment that is to be modified and click on Actions to select Submenus
Title segment determines the Menu names. Link options determine which page the menu segments are linked to. The page you have created and want to add can be linked here. More detailed information on creating new pages can be accessed from here.