when logged into aimoo
go to support
I added like 8 subcatagories easily.
when logged in.
in your forum/group
option toward the top left of yur forum
forum preferences
forum management tab
catagory
now u can add new catagory (name it etc)
or do a sub catagory under general.
if sub catagory name it and add a description.
u can change the order of the subs or even catagories
even if u screw up. u can always change or move a catagory or a sub
thats just the basic idea of it