How to unlock Jobs ?

[Apoc1216]

As someone who just unlocked Monk I can explain it:

Once you have the requirements met for the job you want (30 of main 15 of sub) you have to complete your MAIN class quest at 30. After you complete it you will see a guild receptionist that has a quest for you. Complete it, and you get the stone for the job. For a complete list of sub classes needed...here ya go.

Bard = 30 Archer / 15 Pugilist
Summoner = 30 Arcanist / 15 Thaumaturge
Scholar = 30 Arcanist / 15 Conjurer
Dragoon = 30 Lancer / 15 Marauder
Black Mage = 30 Thaumaturge / 15 Archer
White Mage = 30 Conjurer / 15 Arcanist
Monk = 30 Pugilist / 15 Lancer
Warrior = 30 Marauder / 15 Gladiator
Paladin = 30 Gladiator / 15 Conjurer

Or at least I think this is right.

[SapphireARC]

When you become your preferred job, does it somehow inform you what classes you can use skills from? Cross class skills? During beta the Legacy players said for example: In order to be a Dragoon you need 30LNC and 15PUG. Once you become a LNC you can use all the skills of LNC and only the shared skills of the PUG. No other classes. However the system has obviously changed. Dragoon requires MRD now instead of PUG but I hear from people that you can keep all LNC skills and use any cross skills from MRD and PUG. Just seems like a crazy amount of info that isnt available to me at the moment. Does all this come to light when you get your job crystal? New to the game so forgive me if this question is answered else where. Thanks.