Board Thread:Support Requests - Designing Your Wiki/@comment-35030037-20180527224014

When creating my mobile main page for my wiki, there are two parts of it that I can't seem to figure out:

"Featured Categories" and "Optional Categories"

My main confusion being how to convert an already existing page on the wiki into a "category". For example, how would I go about converting this into a category so I can list it in my Featured Categories section?  