Anyone know how I can make a clan? How do I get a custom clan logo?
"Clans" are built into the game, and you must select from the six available clans.
If you are referring to player organizations, these are known as "Hero Bands" and "Hero Leagues". You must join a clan to create a Hero Band (HB), and Hero Bands can only include characters from the same clan. Up to five Hero Bands from the same affiliation (Black Band or White Band) may join together into a Hero League.
Custom HB logos were planned at some point, but the feature has been "Coming Soon" since long before our service began. They may arrive someday but I would not count on it being any time soon.