Advanced forum: How to modify template of forum list page?
When I had to do this I found there are lots of template files and it's not obvious what controls what. I ended up putting die() in each one to find out which template file was used for each view, and then a case of trial and error to make the changes I wanted.

When you have worked out which files need editing then you should copy them from:

/sites/all/modules/advanced_forum/styles/naked/advanced-forum.naked.TEMPLATE_NAME.tpl.php


to your theme at:

/sites/all/themes/YOUR_THEME/templates/advanced-forum.naked.TEMPLATE_NAME.tpl.php


Any files here will override the ones in the advanced forum themes folder.