As we know The summer seasonal event: the Moonfire Faire has released, but the time is limited this event is only available from August 8th, 2017 at 1:00 a.m. PDT to August 26, 2017 at 7:59 a.m. PDT. Below is the guide if you haven’t get it yet. Hope it will be helpful for you.
At first you should go to Limsa Lominsa Upper Decks ( X: 11.5, Y: 13.8 on the map) and speak to the NPC Mayaru Moyaru, and then you’ll get a quest named “The Isle and the Faire” it’s requires 30 level. Then continue the follow steps:
1. Travel to Costa del Sol
2. Swim to the Isle of Endless Summer (located at X: 36.7, Y: 31.0)
3. Speak with Haermaga
4. Speak with P’obyano
5. Speak with Jiriri
6. Use firework mortar on cannon (X: 37.4, Y: 29.4)
7. Report back to P’obyano for completion
In order to get more Faire Vouchers you need to Repeat the quest on the Isle of Endless Summer for getting some special items. If you are 30 level you can also back to “The True Meaning of Summer”, it will reward you full set of faire clothing and the seasonal achievement.