And so I give you, How Not to Dress French
Some of these should be fairly obvious, but you should avoid:
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The beige trench. I have yet to see a european woman in this, worn wrong, it can make you look like "Columbo" the detective (google it). And honestly, I think it's boring as hell. There is nothing particularly "un-French" about a trench however, but if you wear one, make sure you have it tailored so that's it's not frumpy or awkward, and opt for one in black with a unique cut, fabric or texture.
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The Breton Sweater:
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Established by French sailors to keep them warm on the high seas during the late 19th century, it gradually trickled down into common French society and in women's clothing, and of course, the American girls had to have it. If you do wear it, wear it in an "American fashion", with gray stripes as opposed to navy, and paired with cut-offs or a leather mini and sneakers.
The Jauntily Tied Scarf:
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In this unfortunate advent of the cotton "summer" scarf used to jazz up an outfit, I think we've forgotten that scarves serve an actual purpose, that being to keep our necks warm. In short, I really think you should only be wearing this when it's actually cold outside.
The Beret:
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Berets are seeing quite a heydey, and I for one could not be more pleased, as I own half a dozen. Nothing adds an air of "I actually put thought into this" in under five seconds to a lazy outfit like a hat, and the easiest one to wear is a beret. I say, simply avoid looking like a francophile by wearing a wool tam variety (like the one above) loped over your brow, opting for the back of the head instead. And avoid the tired hipster look by not pairing it with a plaid shirt and skinnies.
Something to remember
You are not French. You are American. There is absolutely nothing wrong with it. There's nothing wrong with emulating international style, but keep in mind your region of origin. If you live in the dusty southwest, a trenchcoat is not going to be practical for your every day life. In the rainsoaked pacific? Stilettos are not your jive. And so on and so forth. Keep your own quirks and body type in mind, instead of wistfully wishing you lived in the street of Montmartre or had the body of some willowy girl in Malmo. Denying who you are and where you live will never look fashionable.