Best Way to Level 2 Classes

[MistakeNot]

Thanks for that. So in class terms, how should I go about it. Should I activate the Puglist class now and continue to level my rogue?
My character is level 44 Lancer/Dragoon, Level 15 Marauder and level 9 Rogue.

It really doesn't matter in which order you level Pugilist and Rogue. Just pick one and level it up first. Or switch between them at regular intervals. Or level them in any other order you may feel like.