The actress admits she's battled skin sensitivity issues -- and is happy to find a product that's worked

Michael Simon/Startraks

If you sit next to Allison Williams on an airplane, we’re just going to warn you: She might start washing her face. In her seat.

“When I fly, halfway through the flight, I like to give myself a face wash,” the Girls star — and new face of Simple skincare — tells PEOPLE. “I just sit there and turn toward the window and use a wipe.”

Yep, she’s that serious about skincare! Which is why joining with Simple — whose products are formulated for sensitive skin — was a no-brainer for the rising star.

“I do have sensitive skin, actually, and it’s been really hard to find products that don’t make it inflamed, or red or dry, or make it break out,” she reveals. “It’s really complicated, but I’ve learned that it’s the case for more people than not. I don’t know how many people have unproblematic skin — that’s rare.”

A lot of Williams’s skin issues come from her job, which obviously requires lots of makeup application and removal. “If you’re an actress — and in some cases, this goes for all women — the only thing you can control about your skin is what you put on your face at the beginning of the day, and what you do when you take your makeup off,” she says. “Otherwise, it’s affected by stress, makeup artists, weather, pollution. The great thing about Simple products is that they protect you against those things — you can wipe it all off at the end of the day.”

Allison Williams Simple Skincare

Michael Simon/Startraks

Williams recently spent a day in L.A. shooting a commercial for the brand, and she found the premise pretty true to life. “It kind of documents a typical day — on my way to work in the morning, getting ready and washing my face, all the way through the end of the day when I take my makeup off and relax.”

But in an ideal world, Williams’s days would go a little differently.

“Lately I find myself working quite a bit — it’s such a blessing,” she says. “But I have a fantasy that I’ll go back to a time when I’m not in hair and makeup every day!” Tell us: What skincare products to you rely on to keep your face flawless?

–Kate Hogan