It seems confused many players that there is not enough currencies when necessary, therefore, we collected information from the forum and shared it with you.
It is a little new to have the quetion, since I only have time to play on weekends. But I'm a level 16, I've been losing more gil than I have been gaining. I haven't sold any items at all yet, I practically just give it to my level quest.
It is crafting that is really greatly profitable on the matter of ffxiv armorer gil, or even sustain by themselves, until you invest a lot of time and gil into it. The first thing you should do is take every craft up to 15. They all give good abilities and doing the level 5, 10 and 15 quests at each guild will give you a ton of shards and low-level crafting gear. Invest the time and effort to level your craft to 50, get all the good cross-class skills and gear up, and do the market research to find out what sells.
As we know, armorer is little weak on gil. You don't really see gil coming in until level 50 anyway. Crafts need money to level and after you level them then the money is involved in. Choose something that isn't armorer if you want money though.
If are really anal about not spending gil on level, you can try buying ore off the mb, and then selling it for benefit. But that's just going to net you anything at most levels, and the leveling is going to be strongly slow and a waste of time.