I'll double post since I hit my text limit XD

Next is Company Seals
1st you'll need to farm some FATE to get those seal, do GC logs to get bonus seals and unlock new rank
once your rank is high enough (I can't really remember though) you'll be able to turn "Green, Blue, Pink" into seals which will enable you to get tons of seals quickly

Gils
I don't really know how to suggest this, but I'd say, DoL is the cheapest and fastest way to make money, since all the investment are, of course, yourself.
crafting might be a bit pricey at start since you won't be able to make HQ stuffs easily, and low lv HQ equipment usually cost just a few thousand.
Spiritbonding is one of the fastest way, but very risky since you might ended up wasting time for a small amount of money