"I’m 45 years old, so I’m not going out like I used to. It isn’t possible—I work, it’s difficult. I started this fine jewelry brand, Stone Paris, 12 years ago, and it takes up a lot of my time. I still go out, but now, it's mostly dinner parties with friends. I think it's very nice to have people over—sometimes, that's better than going out. But when we do, we love Japanese food. There are a lot of great Japanese restaurants near my office. I like Takara, which is one of the first ones, and Yamamoto or Kinugawa. Some weeks I'll go out five times for dinner, and then the next week I won't go out at all. It's nice to switch it up. [Laughs]

Whenever I dress up, I put on jewelry—but jewelry is something I wear all the time. I like things that you can wear during the day into night, and not have to change. I sleep in it, too... I shouldn't. I'm always wearing jeans, usually J Brand, or black trousers. Sometimes I wear a dress if I have to. I like Saint Laurent, but unfortunately Hedi Slimane is gone so it won't be the same. I think he made things that were very easy to wear—you can wear them all the time. I like that ease.

Before I go out, I'll wash my hair. My favorite shampoo is Aveda. For a long time it wasn't in France, so I had to buy it in the United States and bring it back. I like using that, or I'll alternate with Leonor Greyl shampoo. My hair gets very, very dry, so instead of conditioner, I'll do a Phyto Phytojoba Intense Hydrating Brilliance Mask for half an hour with a towel after I wash it.

My makeup is simple, too—I wear Laura Mercier's Secret Camouflage in SC4, every day. Then I use MAC Translucent Powder because I don't like to be shiny. At night I put Nars Kohliner on all over my eye, and then I use MAC Brow Set gel. I've never tweezed a day in my life. I don't like when my brows are thin—but that's just my taste. I don’t like lip gloss, because I hate sticky. Only matte. I would wear nude, brown, never pink and never red. I would love to wear it, I think it’s beautiful when I see someone wearing red or pink lipstick, but if I put it on I think everyone will stare at me. [Laughs]

To be honest, though, I try more skincare products than makeup. At the end of the night, I wash my face with Sisley—I just love the smell. Nuxe Comforting Cleansing Milk is good too, so I always use one of those two. And I love the Sisley Express Mask, but typically, I just use Sisleÿa cream. It's quite rich, but my skin gets very dry. If I don't use that, I'll use the Caudalie Polyphenol Overnight Detox Oil. And then Institut Esthederm Paris Osmoclean Lightning Buffing Mask is good to do once a week. And that's basically it. I think it's very elegant to have a few things that work. My friend Inès de la Fressange, I've known her since I was young. She always has a simple look—and I think that's beautiful."

—as told to ITG

Marie Poniatowski photographed by Tom Newton at her home in Paris on March 9, 2016.

Next up: Annelise Michelson believes in perfume monogamy, Sandy Liang doesn't believe in expensive lipstick, and Aurèlie Bidermann just wants big hair in the Top Shelf After Dark.