Really dumb question about titles...

I've looked around and I know this has an extremely easy answer so I'm sorry in advance.

I can't figure out how to make section titles for my forum. For example:

General <-TITLE
General Discussion
News
Updates
FAQ

Members <-TITLE
Headquarters
Suggestions

Right now, I have "General" and "Members" as a Category and General Discussion, News, Updates etc. as Forums... But when I go to my forum page "General" and "Members" doesn't show up. It just lists all of the forums like this:

General Discussion
News
Updates
FAQ
Headquarters
Suggestion

Can you tell me what I'm doing wrong?

Display>strucuture and hierarchy
Split categories on index: medium
save.

See if that works.