Jennifer Love Hewitt attends the "Mickey Through The Decades" collection celebration at Walt Disney Studios on July 13, 2013 in Burbank, California. Credit: Jason LaVeris/FilmMagic

It's been years since she starred in '90s staple Can't Hardly Wait, and Jennifer Love Hewitt tells Us Weekly that she's learned a thing or two about patience in that time. The first-time mom, 34, explains that she's having a smooth pregnancy so far because she's choosing not to stress about the unknown.

"I think most people, when they're getting ready to be a mom, they go, 'Oh my gosh, I have to have all of the answers right now,' but every kid is different, every parent is different and every child and parent relationship is different, so you just sort of have to wait until you're in it and do the best that you can to try to be Zen in the middle of it all," Hewitt told Us at Old Navy's "Mickey Through the Decades Collection" launch in Burbank, Calif. on Saturday, July 13.

Hewitt, who is expecting her first child with Client List costar Brian Hallisay, rocked a grey Mickey Mouse tank top and dark jeans at the Disney and Old Navy event.

The expectant mother shared her secrets to a stress-free pregnancy, telling Us that she is working with a trainer on a regimen that includes yoga and pilates, as well as "cardio and weights so my arms are strong to hold the baby."

And, Hewitt tells Us, the couple is opting to keep an element of surprise around the baby's birth (she and Hallisay don't know the gender of the baby).

"You sort of have these pictures in your mind of what [the baby's going to look like]," she said. "I'm really excited to see what he or she is going to look like!" 

Us Weekly exclusively broke the news of the actress' pregnancy in early June. Hewitt and Hallisay began dating 16 months ago when they reconnected on the set of their hit Lifetime show after previously appearing together on the short-lived NBC series Love Bites.

"I'm off work for the moment, for the summer," she told Us of getting some rest during her pregnancy. "It's a really happy, positive time, which I'm grateful for."