Use this procedure for creating a menu item that does not link to a page on the site. To add a site page to the menu, edit the page and assign it to the primary menu in the "Menu Options" section.
1) Log in.
2) Click on "Add a Menu Item" in the "Quick Links" menu or in the "Administrator Links" menu, go to Menus and click the "Add menu item" tab. (admin/build/menu/item/add/2).
3) Enter the title, path (URL), and description (optional) of the web page you would like the menu item to link to.
4) Select "Primary Links" in the "Parent Item" field (this will probably be the default)..
5) Assign a weight to determine where in the menu the link will be displayed.
6) Click "Submit".