See the squadron button under your stats when you first see the chat? Click it, then search International Airforce, then Click join. If anyone else need assistance please pm Pie of Jerry (go to his profile and message him) thanks.
-From gossip thread of "HOW TO JOIN A SQUADRON"
This is a step by step thread (which I hope will have screenshots by tomorrow) of trying to join a squadron [I've been asked this question MANY TIMES]
1)Open dogfight and hit Multiplayer, this takes you to the wc lobby
2)Look underneath your stats for a button labeled "Squadron", Click this button and it will take you to a search area
3)Type which ever squadron ex: International Airforce and click the search icon, this brings up a list of squadrons
4)Click said squadron and I should take you to the members list (with other button options just above the list)
5)Click the button labeled "Join" and you are finished!!!