Roles beat friendship
A twenty-player clan is an organisation, not a group chat. Someone owns farming, someone owns building, someone owns the raid calendar, and one person has the final word when those three disagree at 3am.
Loot rules, written down
Decide before wipe who can take what from which box. Ninety percent of clan collapses trace back to an unwritten rule that two people remembered differently.
The rotation
Split the roster across time zones deliberately. A clan that is online twenty hours a day is functionally unraidable; a clan where everyone plays the same four hours is a scheduled event for its enemies.
Know when to shrink
Twenty is not automatically better than eight. If half the roster is idle, you are carrying the raid appeal of a large clan with the defensive coverage of a small one.
Put it into practice
Reading is cheaper than sulfur.
Every technique in these guides was learned on the servers below. Pick a region and test it tonight.