Quote Originally Posted by kcj View Post
As I've recently discovered, pretty much everything crafting related is tied together. If you do one, then you really have to do them all.

On the flip side, once you've gotten them unlocked; you can usually level them (abet slowly) through Grand Company Supply and Provisioning Missions.
Tradecraft leves are the fastest way to level your crafters without question. However, they are limited to allowances and you can burn through them quite quickly if leveling all the crafters. For this reason it is important to turn in HQ only as they give a large bonus to exp. GC turn-ins are great too, and again, be sure to turn in HQ. The starred items give ridiculous exp, and an HQ turn in doubles it. More methods involve tribe quests relative to your level, and log completion. The latter is the slowest method and floods your inventory. However, if you go the really slow route and gather all your materials, process them towards log completion, AND sale everything, you'll come out on top with a crap ton of gil. This method does not require tradecraft leves.