It was "95 percent her, 5 percent me," The Mortal Instruments: City of Bones actor Kevin Zegers told PEOPLE about the planning leading up to his Aug. 4 New Jersey wedding to his longtime girlfriend, talent agent Jaime Feld. Prior to the big day, Zegers said the seating chart for the 250-person guest list was the biggest challenge. "She's an agent, so a lot of her clients are going to be there. We're figuring out whether to put my aunt and uncle, who live on a farm, next to some of her clients," he explains. "It's a very fine balance."