In America, twin sets may be traditionally stylish, but in France they’re more likely to inspire, well, ennui, a French author, Mireille Guiliano, said.

Last year, Ms. Guiliano, took on the gaping gastronomic divide between French femmes and the more zaftig American women in her best-selling book, “French Women Don’t Get Fat: The Secret of Eating for Pleasure.” Now she’s back with a less sharply focused book on how American women can develop the classic style, refined palate, and shoulders-back confidence of Gallic gals.

In “French Women for All Seasons: A Year of Secrets, Recipes & Pleasures” (Knopf, $24.95), Ms. Guiliano demystifies the French je ne sais quoi. She does this by offering readers step-by-step directives on everything from tying scarves to hosting cheese-tasting parties to taming frizzy hair to braising fennel.

Ironically, “French Women for All Seasons” emphasizes a skill with which women stateside are already be well acquainted — branding, though not in the American “drink Coke” or “wear Nike” sense of the word. “You are your own brand,” Ms. Guiliano writes. “What’s your brands DNA, and how is it expressed? Clothes? Jewelry? Makeup? Hair? Voice? Laugh? Touch? All of the above, and more.”

Ms. Guiliano invokes the Oracle of Delphi as the prescription for successful selfbranding: Know Thyself. She said her countrywomen seem so effortlessly chic because they’ve developed an awareness of what they look good in — and what they should not attempt to pull off, even if it’s a seasonal “must-have.” “French women love fashion, but they don’t follow fashion,” Ms. Guiliano said in an interview.

She explained that French women have co-opted fashion to hide their figure flaws. “It’s up to you to decide what looks good on you,” she said. “I don’t wear jeans. I have nothing against them, but I don’t like myself in them.”

Perhaps the most common fashion faux pas among American women is extreme accessorizing, Ms. Guiliano said. “When I was 16 my mom said to me, ‘Mireille, don’t overdo it.'” she said. “There’s always one thing that’s too much.”

On the subject of accessories, Ms. Guiliano said the topic of her next book would be handbags. While mega-purses like the Fendi Spy and the Chloé Paddington may be objects of desire, the author favors plus petit sacs. “How much do you really need when you leave the house each day,” she said. “Clutter doesn’t help you feel better.”

Smaller purses and fewer accessories are all part of Ms. Guiliano’s “less is more” philosophy that permeates “French Women for All Seasons.” The book is peppered with three-step recipes; easy-to-follow tips for buying, storing, pouring, and tasting wine; practical advice for building a small, but versatile, wardrobe.

And while some French women do get fat (a recent study showed that 42% of France’s adult population is overweight) and some may wear twin sets (the popular French label Agnès B stocks them), Ms. Guiliano insists that American women can learn a lot from their trans-atlantic counterparts when it comes to food, fashion, and feeling good in their own skin.

What can French femmes learn from American women? “How to become entrepreneurial,” Ms. Guiliano said. “How to better combine work and family life because in so many ways American women are way ahead of us.”

She paused, then added: “The idea of brunch — that’s something we stole from you. What a fantastic idea!”