A short scene will play out when you enter Guadosalam. Afterwords, Rikku will teach you how to customize equipment! As long as a weapon or piece of armor has an empty slot, it can be customized. Add abilities using items from your inventory.
The first door on the right leads to an Inn. You can rest there for a night, or just save at the Save Sphere. You can also learn more about the Farplane and the Pyreflies from the historian in green.
Return to the outside area of Guadosalam. To the north is Seymour’s Mansion, and to the right of the door is a treasure chest containing a Mega-Potion.
You may want to look around Guadosalam before continuing the story. The house to the west contain the Al Bhed Primer vol. XIII and a treasure chest holding 3000 Gil.
The house to the south is actually a shop. You can buy weapons, armor, and items from the Guado or from O’aka. The items from O’aka will be cheaper if you lent him enough Gil early on.
Travel up the bridges and walk south beyond two conversing Guado. You’ll find a treasure chest containing an Ether to the right of them. With everything take care of, head to Seymour’s Mansion on the ground floor.
Seymour’s Mansion
Before speaking with everyone in the entrance hall, head up the stairs and search for a treasure chest containing two Hi-Potions. Interact with your entire party to enter the dining hall, then speak with them in the dining hall to continue the story.
After hearing Seymour’s proposition, exit out of the mansion and walk south to hear more about the party’s thoughts. Your next objective is to climb to the top of Guadosalam to reach the Farplane.
Road to the Farplane
Walk a short distance down the path. If you search a corner on the left of the road, you can find a hidden treasure chest containing eight Lightning Marbles! Travel up the path to learn a little more about the Farplane from the party.
Farplane
Walk over to Wakka to finally see Chappu. This will also power up Tidus’s Brotherhood sword. Speak to Lulu next, followed by Yuna before leaving the Farplane.
Return to Guadosalam
To continue the story, walk down to the party in front of Seymour’s Mansion. Talk with Lulu several more times and tell her how you feel about the girls in the party.
Walk down the path to the west to start another scene. This time you’ll talk with Shedlinda. Return to the party afterwords to end the story in Guadosalam. Your next destination is the Thunder Plains down the path to the southwest.