Mark-Paul Gosselaar and Catriona McGinn
09/19/2011 at 06:30 PM EDT
Mark-Paul Gosselaar and Catriona McGinn are still planning their wedding. But they know one thing: It's not going to be small.
"Once we find a place where we want to have it, then we'll set a date. But it'll be a grand event. A lot of family," the actor, 37, tells PEOPLE.
The Franklin & Bash
and former Saved by the Bell
star says they're not leaning toward having a theme, but they do want to make it "a family affair."
"She has a great family. And we want to celebrate," he said in an interview after finishing the Nautica Malibu Triathlon earlier this month.
Gosselaar got engaged
to McGinn, an advertising executive, this summer.
"How do you know they're the one? You just know," he says. "I feel fortunate enough that I found her and we found each other and that we can start a life together."