Hm.
Since it's outdoors in the summer, and it's bound to be hot, I'd go for a lightweight Tommy Bahama Port-O-Fino long sleeve white linen shirt. White will keep you cool in the sun, long-sleeves will make you look sharp.
With Tommy Bahama St. Thomas silk twill khaki pants
Steve Madden Novo tan shoes
Fossil Evan Jean belt
Good luck, and have fun!