Really not that hard, as TristanX and Risvertasashi said. Once you get your first job to max level (currently 80), gearing up and leveling other jobs becomes fairly easy with a combination of Dailies, Duty's, Fates, PoTD, HoH and Beast tribe dailies levels will practically fly by. There is of course the "Pay" option by visiting the mog station and just buy the boosts, but honestly I prefer to actually play and level the class (Though I have payed SE for job boost for alts, but not my main).