Questions about the game.

[Niwashi]

1)Grind FATEs (these are the events marked with purple icons on your minimap), you need to be part of a grand company to earn seals.
2)Complete guild leve quests for your grand company

3) Duty Roulette

And if you also do any crafting/gathering, there's:
4) turning in supply/provision missions at your GC headquarters