Making Gil Efficiently?

[Slatervonjager]

sell all the "Plundered" gear I find.

Oh no no no, save that gear, because you can trade gear in like that, or the aetherial gear, for GC seals when you achieve the rank of Sergent second class.

[Akuha]

Oh no no no, save that gear, because you can trade gear in like that, or the aetherial gear, for GC seals when you achieve the rank of Sergent second class.

I heard someone say something like that when I was doing a Copperbell run once, when they asked why I never pick up any aetherial gear (I don't because it's not tradeable, I consider it junk if I already have something better). After that I went to my GC's HQ and looked around, but never found anything resembling a gear trade in feature. I'll be sure to save up my seals for promotions and start doing that.

[BlossomRose]

Run CM or Praetorium a lot. Assume you manage to do 2 runs per hour, that's 200 tomestones per hour. Each 125 tomestones can net you an item you can resell for, depending on your server, anywhere between 10k gil to 50k gil.

Cash racks up insanely fast.

[Brutallyn]

can also farm components that crafters need, like diremite webs (but there are of course plenty other things to farm)
Webs sell for 400-500 gil each on my server.

Brut