WHEN NEW YORK CITY comedian Jared Freid appeared on “The Tonight Show Starring Jimmy Fallon” this fall, he recounted that, back in college, he and his friends would layer on several colorful polo shirts, collars popped—a fashion choice that left Mr. Freid resembling what he ruefully called “an aggressive tulip.”When it comes to layering clothing—that stylist-approved way to keep warm come winter and spruce up the separates in your wardrobe by combining them in fresh ways—it’s easy to mess up even if you’ve never been a noughties frat boy. Done thoughtlessly, it can leave you looking like Joey in the “Friends” episode when he dons every single article of clothing that Chandler owns. Here, five common problems that inept layerers run into—and what to do instead.

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