Go to Settings -> Menu

Adding a Page to Menu
- Select the item that you want to add by clicking the checkbox next to it.
- Click the "Add to Menu" button.
The new item will automatically show up at the bottom of the menu structure. Drag it to the appropriate spot.

Changing Name of a Menu Item
- Click the downward facing arrow on the menu item.
- Find the navigation label and modify the text.

Removing a Menu Item
- Click the downward facing arrow on the menu item.
- Click the "Remove" link.
