[@robkk Moderator 10 years, 12 months ago]

You can also create categories then add your forums under that by setting the parent of the forum as the chosen categories.

To have a better layout use this loop-forums.php file here.

https://github.com/robkk/bbPress-Hierarchical-Forum-and-Category-Layout

Download it and place it into your child theme in a folder called bbpress.