like Felis said you will need to do a darkhold quest to gain acess to AV for some of your AF, after that it is spamming Ifrti,moogle, garuda, AV and CC. During down times for the endgame, level other classes and or crafting/gathering. There is also hamlet defense which you will need to grind for seals for your relic weapon as well as getting a base weapon made for relic. here is a guide you can start for your relic weapon http://xivpads.com/?-Guides&Guide:_AF_Weapons also grinding GC seals for promotions and gear is always good.

Edit: oh there are also strongholds to do as well for some gear.