Finish up the story, unlock end-game dungeons, grind for gear (Labyrinth of the Ancients, then Syrcus Tower, then World of Darkness, Primal Extreme accessories and weapons, and keep saving up for Soldiery/Poetics gear). You can also start a relic weapon, but at this stage with the expansion fairly close I'm not sure if the grind is worth it.

Furthermore, I'd recommend taking a look online about the best rotations for each job, you may need to level some other jobs to get the right abilities.