On Joining the Flying-Monkeys guild you are initially set to ‘Unititated’ and you must undergo an initiation test to become a true Flying Monkey. On the EU server this is held in Cappy’s Coldharbour house and on the NA Server it is done in the guild house.
To become a true Flying Monkey you simply have to jump off a rather high spiral staircase and plumet down to the ground snf that makes you s true Flying Monkey and the promotion allows you access to the guild bank.
However, if you manage to survive the jump, not many have so far, then you become a legendary Flying Monkey in the guild.
Take a look at Cappy doing the initiation and surviving the jump 🙂