"I'll just be working. I know that I have a 5:30 am pick-up but that's not bad," the actress – who is currently on location for her next film, Untitled Elmore Leonard Project, in Connecticut – tells PEOPLE. "I'm lucky; I'm very happy to be working!"
"This birthday is going to come and go, which they all seem to be doing these days," she adds. "Wasn't it just my birthday? I have like windburn from this year."
With the production set to last five weeks, Aniston has relocated to the east coast and continues to fulfill her duties as spokesperson/co-owner for Living Proof hair care.
For her role in the film, she opted to wear a shorter, light blonde wig instead of coloring her famed tresses. "It's so nice to wear a wig. It's like putting a hat on," she says. "I've been using our conditioners on my hair underneath and it's great to be able to watch your hair actually grow."
The actress, who got engaged to screenwriter Justin Theroux last year, says her idea of a perfect birthday "would be a walk in the city, brunch somewhere, see a movie, have a great dinner."
For more of our exclusive interview with Aniston, including how she maintains that amazing bikini bod, pick up this week's issue of PEOPLE, on newsstands Friday