Most of my gil is made through spiritbonding. Since you're not 50 yet, buy the 35+ crafting/gathering gear from the vendor NPC in the Observatorium area in Coerthas (Ignore the accessories, unless you can craft them. You can at least buy Wolf Earrings from the NPC in Ul'dah near the marketboard.), get into a spiritbond party at Urth's Fount, kill them mobs, get the moneys.
As long as the gear is 35+, it'll spiritbond in half an hour or less, if the party is pulling consistently.
Once you're high enough to wear the 45+ gear, switch to that for a chance at materia IVs.
Materia prices have been dropping, but you should at least double what you spent. Get a single Command IV or Control IV, and that's 200k~ right there.
As long as the gear is 35+, it'll spiritbond in half an hour or less, if the party is pulling consistently.
Once you're high enough to wear the 45+ gear, switch to that for a chance at materia IVs.
Materia prices have been dropping, but you should at least double what you spent. Get a single Command IV or Control IV, and that's 200k~ right there.
