Menu Item Definition
First you must decide which menu you want the menu item to appear on. The red headings in the menu bar on the left correspond to the names of the menu items. So, for exampe, if you wanted to create a new item under "Classmates" then go to:
A Menu Item Manager screen appears, which displays all of the items on the menu. To create a new menu item click on the "New" icon in the top right. The first step in creating a new menu item is to select the menu item type. The basic idea here is that you have to identify the module within Joomla and its extensions that is going to generate the content for your menu item.
The simplest choice is probably Articles->Single Article. This is the format for a menu item that is going to display a text/images page that you create.
Once you select the menu item type, you will see a page that allows you to make the appropriate configuration choices for that type of menu item.
NOTE: When you create a new menu item pointing to an article, you must select an article before you can save the menu item. This is an incentive to create the article first. Otherwise you have to select some random article, then write the article, then go back and edit the menu item to point to the correct place.
ATTENTION: I have had trouble when creating new menu items or changing the type of existing menu items. The problem is that the proper parameters for the menu item type don't appear on the right side of the page. If this happens to you try another type of browser - i.e. Firefox instead of Internet Explorer, or the other way around. That has always fixed the problem for me. I'd be interested to hear if other people have this problem.
WARNING: In Nov. 2019, I found that I could not change the list being displayed by a menu item using the administrator site. I wanted to change the menu item that pointed to the current reunion attendees (listid=6) to instead point to the prior reunion attendees (listid=7). I could see the listid in the menu item page but I could not edit it. I got around this by using CPannel to access the database directly. I changed the link field for the j16_menu entry for the appropriate menu item. This worked successfully. If you have trouble with this please contact me! Bill Bean (email@example.com).