WordPress has an easy system for creating and using menus but it is not always obvious how to work with the menu system.
In your WordPress menu choose Appearance | Menus. If you don’t see Menus then you might not have the rights to access the menu system so you will have to contact your administrator and ask them to give you the correct permissions.
Once you are in the Menu System you can select the menu you want to work with and add new items, delete old ones and even drag items to reorder them on the menu.
Here is a Video Tutorial that may be of assistance
This guide has details on creating a menu, adding items, deleting menu items and creating custom menus.
You can even create your own custom menus in WordPress
1. To create a custom WordPress menu, log in to your WordPress site and click to expand the Appearance menu on the left side of the WordPress Dashboard.
2. Click on the Menus link in Appearance menu. You’ll now be in the Menus editor page.
3. Enter your own custom menu name, and click Create menu.
4. Now you’re ready to add menu items from the boxes on the left hand side of the page, such as pages, categories and links.
5. When you have your menu items arranged in order, click Save Menu. You now have a new navigation menu that can be added to any menu location on your WordPress site.