Adding Menu Icons

I’ve installed the plugin Font Awesome 4 Menus but when I try to add custom links to my menu I’m still only getting the social icons. I have tried enabling CSS classes under APPEARANCE > MENUS > CSS CLASSES but I still only have those few social icons to choose from. I want to add a custom menu to my sidebar (which I know how to do) but I want to be able to choose from all of the Font Awesome Icons and not just the social icons. Please help.