Board Thread:Help and Support/@comment-11205947-20130803002452/@comment-5142578-20130804203408

It's no different than adding a category to an article. If the category doesn't already exist, it will be created once you put the category in.

For example, say a location is the first moon colony on SFW to be introduced, and therefore a Moon Colony category doesn't exist. Simply type in "Moon Colony" in the category box, and once you enter it, it should be created automatically.

I hope this helps. By the way, which category are you wanting to make? I could probably do it for you if you wanted to.