You may have noticed, under your signature in posts, it shows DRN "Chapter: None"
To make your Chapter Show-Up, go into "your cp", then "profile" and enter the name of your chapter, just as it appears in these forums. No, you can't make one up. The name has to be entered EXACTLY as shown here.
The only forum that I notice the "DRN Chapter: None" appearing after the standard sig is that certain forum that was recently added. Also, under my CP, I can't find the field for entering your chapter.
FWIW, I use the "Bright Ad Free" skin. The forum that I do see the "DRN Chapter: None" does show ads; it appears to ignore my "ad free" skin selection. May have something to do with it.