In fashion, a lot of lip service is paid to creating a personal style, yet somehow everyone always seems to wear the same thing. Enter Robin Brouillette, iconoclast. In the 1990s, her unstructured, body-hugging silk dresses drew admirers from Sydney to L.A., including Cameron Diaz and Michelle Monaghan. When 9/11 forced her to close her ultrahip Stanley boutique in lower Manhattan, Brouillette sought refuge in travel and ended up in Bombay, where she had a design epiphany: extravagant beading and embroidery. Now based in San Francisco, she just opened her first boutique devoted exclusively to her ornamented dresses, in Potrero Hill. Robin Brouillette: 1325 18th St., S.F., 415-206-9335, robinbrouillette.com

Ever since Reese Witherspoon showed up in a yellow Nina Ricci at the Golden Globes last year, short dresses have been dubbed the new gowns. True? You are asking the wrong person. I try not to look at fashion magazines. The minute I start seeing dresses in magazines, I second-guess myself. To me, everything is in. I don’t pay attention to length. I am less involved with following fashion trends and more involved with making beautiful things.

Your clothes are worn by women from their 20s to their 50s and beyond. Yet we read that women of different ages shouldn’t be wearing the same dress lengths and silhouettes. I think confidence and style are the answer. If you are 50 and can rock a mini—within reason, not crotch-level—then rock it. There is a solid argument for age-appropriate dressing, but I think it goes back to style. If a 50-plus woman is wearing a cocktail dress that is both sleeveless and above the knee, shows perhaps too much cleavage, and is trendy, too tight, too loud—then sure, it is a complete aesthetic assault.

If you’re on the mature side, what are some tricks to dressing younger in a good way? A chic option is to pair a short dress with opaque tights and high heels. If a woman is wearing a dress that is a few inches above the knee but is well cut and timeless, then she will look stunning. A slim caftan is also very elegant and very appealing to an older age group—it can hide a multitude of sins. It also makes a great dress for entertaining at home. But I love to see a gorgeous woman tastefully showing her cleavage or fabulous legs—no matter what her age. Vivienne Westwood is one of the sexiest women alive. She can pull off anything.

That said, should older women avoid certain fabrics? Women over 50 should avoid a thin, almost lingerie-weight silk in dresses that many 20-year-olds can happily pull off.

Setting aside age, who should wear what, depending on height and body type? A woman really has to look in the mirror and recognize her strong features and flaunt them, and vice versa. If you are wide in the middle but have great legs, choose a style that is boxy around the middle—not a fitted waist—and short. A dress that has a fitted torso with boning accentuates a slender waist.

What about dresses cut on the bias? It can be an incredibly flattering silhouette for many women. A long, bias-cut dress looks especially great on someone who is tall and not that curvy. But you have to do it right. After being cut, a dress has to be hung for at least 24 hours so that the bodice settles. When you see a dress with little bubbles on the side, it wasn’t sewn right.

You design a lot of ornate and beaded clothes. What’s the best way to wear them? I loathe the idea that someone would save my dresses for something formal. I wore one of my beaded tunics over skinny jeans to dinner with a girlfriend last night, and though it stood out, it looked fabulous.

Since you’re obviously a maverick charting your own stylistic course, how do you suggest others find their own fashion muse? Everyone has a style. I think that one’s style changes and develops naturally, or at least should, based on one’s lifestyle, career, age, travel. Whatever makes someone look beautiful and feel confident is the right style for that person.

Some New York designers send their assistants to thrift shops for inspiration. Where do you find yours? It’s very clichéd, but I’m inspired by travel and by books and by writers and film—things that have meaning and depth. I do take the industry seriously, but I think fashion should be fun and timeless. You can buy a piece and wear it in 20 years. It’s not like flipping through a book and saying what the color is for next season.

What do you think of cheap chic, as epitomized by H&M and Target? You can only go so far with it. You can’t knock off an intricately beaded or embroidered dress well—you can’t possibly make it like this and sell it for $50. I love the mixing of the high and the low in one look, but I do think "fast-food clothing" is on its way out.

Why? People want something that is special. I would rather see 10 unique pieces in my closet than 200 that I’ll throw away every season.

So, what is in your closet? Levi’s. Old Helmut Lang jeans. Christian Louboutin shoes, and Repetto ballet flats—I have tons of them. I have a black canvas Gucci tote I use all the time.

You spend so much time in Paris; what style secrets have you picked up from French women? The art of simplicity and timelessness. They are understated and so chic, and you can see that in nearly every French brand. You don’t walk the streets in Paris passing loads of shops with throwaway, trendy, one-season clothing.