First and foremost I have no great understanding of abyssea, so I will say I have no opinion or standing on how I should approach this, so if that is an issue for me asking, I am only taking this as suggestion and advise, since most of endgame is at the Abyssea aspect of the game.
I know If I want to be more effective in Abyssea I need to collect Abyssite, And get my Atmas, but I have no idea how to get worked into it.
I read up wiki but it is not very clear on exactly what to do.