"After the war I returned home restless, decided to go east to learn the bonds business."
You know I just bought a hydroplane, do you wanna go out one morning Old Sport?
"Old Sport" gets invited to one of Gatsby's parties for the first time, and this is where Gatsby and "Old Sport" meet for the first time.
This also where Gatsby invites "Old Sport" out with him to take a ride in his new hydroplane.
Gatsby and "Old Sport" become closer. Gatsby is still in love with Daisy (Old Sports first cousin), so he get his to invite her over for tea, so he can go to his house while shes there and he can see her.
Daisy and Gatsby were driving, and daisy ran over her husbands lover.
Gatsby has a funeral but only "Old Sport", Gatsbys dad, and his assistant show up.