From Pierre-François-Pascal Guerlain’s first bottled scents, unveiled on the Rue de Rivoli in 1828, to the game-changing launch of Coco Chanel’s iconic No. 5 in the roaring ’20s, the French love of fragrance runs deep. Who better, then, to ask about perfume—when, where, and why to wear it—than a Parisienne whose laissez-faire approach to beauty has become a full-blown global phenomenon in recent years.

Enter Ines de la Fressange, the fashion icon and muse, who is living proof of the Gallic dedication to scent. “Every day!” she exclaims with a laugh, when asked how often she wears perfume. “Even if I stay home alone.” Here, de la Fressange breaks down five simple rules to wearing perfume à la française, from the importance of subtlety to the reason why she’ll never change her signature scent.

Rule No. 1: Find One Scent and Stick to It

“French women are very faithful to their perfumes. They wear the same one for years and do not change it, whether it’s morning or evening, winter or summer. I think American women like to have several. They appreciate new perfumes and buy things that they discover in magazines or at department stores, where quite energetic sellers are jumping on them. This does not exist that much in France. Don’t ask me about new perfumes: I generally hate them. I find them too aggressive, with too much iris, grapefruit, or I don’t know what!”

Rule No. 2: But Let Your Perfume Evolve With You

“When I was a young girl, I started to wear this patchouli scent—very ’70s!—until my grandfather became totally upset and told me a young girl shouldn’t wear this type of heavy fragrance. So he offered me Sandalwood by Floris instead. Later, a friend at school was wearing Chanel No. 19, and I so admired that she would have this kind of grown-up style that I copied her—funny that, later, I worked for Chanel, which is where I learned a lot about perfume.

In those days, I wore Chanel Cuir de Russie, which was available only at Rue Cambon, until my husband stole it from me! Now, and for a long time, I’ve been wearing Mitsouko from Guerlain. Very often, cabdrivers give me compliments, and my children would hate me if I even thought of changing it!”

Rule No. 3: Keep It Subtle

“French women do not wear very strong things. Perfume should be discreet, like a little secret. I spray perfume around the neck, on my wrists, and on my scarf. I guess I saw my grandmother [doing that]. She used to like perfumes so much that when I visited her at the hospital once, she only had flasks of perfumes on her table and not one medicine. It was a dainty way to receive visitors.

Personally, I like musky scents and hate ones that smell like food—vanilla, chocolate notes—or that remind you precisely of something. I think French people appreciate brands that are not so famous but admire great quality, like Frédéric Malle or Serge Lutens. However, Shalimar by Guerlain is still very successful.”

Rule No. 4: Never Mix and Match

“When you know a little about perfumes, you learn how difficult it is to make them and how important the work of the “nose”—the guy who imagines the fragrance—is. For instance, they need some bases that don’t smell nice to mix with other ingredients to reach excellence, so never think you can mix different perfumes yourself—it won’t work! Listen, French women are not perfection! [laughs]. But French brands are great . . . trust them!”

Rule No. 5: Fragrance Your Entire Life

“In my drawers, I put potpourri from Santa Maria Novella; in my car, Cyprès from Diptyque, which is a house perfume; and I also have perfumed sticks from Rigaudin the entrance of my home. I keep fragrance in my office, and I am an addict also for perfumed candles, which I travel with. When it comes to [fragrance], I never go out without it!”