We need updated instructions for Joomla 3.x

The answer to copying a menu in Joomla 3 is:
- Create New Menu Item which will be your Mobile Menu
- Go to menu where the items you want to copy are.  Use the check box to select which items you want to copy.  Choose "batch" and click on the "copy" button and select the new Mobile Menu for the location to copy. 

I have created Mobile Menu.  I have created separate modules for each mobile type as directed on page 2 of this thread.  But when viewed on mobile, there are no items on the menu.  I presume you do have to assign Mobile Menu to module position, but which one, when you have created 4 different modules?  Do you need 4 menus to correspond with the 4 modules?  I will try that next.