How to create child categories/subcategories?

KroxenGames

Hello, I'm new to this and recently I purchased a hosting service which included vanilla forums. So far I like it, but there's this one problem...how do I create child/subcategories? I clicked on one of the help links and it showed this image that there are child categories, but it doesn't explain how to create them. Can anybody help me? Here's a screen shot-

KroxenGames

never mind, I figured it out.

UnderDog

Please feel free to share what you've found.
If it's easily explainable, please explain on the Vanilla Wiki too :-)