Festive Fashion for Christmas

SANTA ISN'T THE ONLY ONE putting on a suit. But with a list of party invites as long as St. Nick's curly beard, figuring out what to wear can be a hairy task. Like the perfect gift, the right outfit requires the right intelligence: knowing the setting, the guests and, most of all, yourself.

Slim-fitting trousers may seem like a good idea--until you're stuck with a too-tight waistband after an eight-course meal. (Beware popping buttons.) The invitation may say smart casual, but if you've never seen your host or his friends in anything resembling a pair of khakis, you might want to rethink the Mr. Rogers sweater. And if you're not used to wearing figure-hugging bodycon numbers, no amount of Spanx will make you feel comfortable in one. So why spend a perfectly enjoyable night distracted by anything other than the good conversations happening next to you?

Here's our guide to dressing confidently--and comfortably--this season, no matter what your style.

FOR HER

Why not bring the party with you this season? While there's plenty of sparkle, sheen and metallic out there, there's no need to go overboard. Think instead in terms of pieces; shine should really only cover one part of the body.

You won't need much else if you wear Givenchy's gold sequined cutout maxi ( GBP4,375), Burberry's draped bronze skirt ( GBP450; both net-a-porter.com ) or Marni's super-luxe feathered skirt ( GBP1,560; marni.com ). Pair with a simple cashmere top and Louboutin's Belle boots ( GBP645; christianlouboutin.com ).

But you don't need sequins to sparkle. In Gucci's elegant floor-length black silk dress ( GBP3,210; gucci.com ), you'll look like you just stepped off the red-carpet. For other party pieces that really pop, try Saint Laurent's mod Gold Guns ( GBP2,000; selfridges.com ) or Miu Miu's crystal-embellished Cady dress ( GBP4,130; net-a-porter.com ). Or invest in a fail-safe dress, like Roland Mouret's paneled midi ( GBP895; brownsfashion.com ) or Jaeger's all-over lace dress ( GBP220; jaeger.co.uk ), that will work hard for the money--and put you at your ease in the process.

Tina Gaudoin

FOR HIM

Greet the season of excessive libations, appetizers and casual banter in style. Though black-tie events may be few and far between, when they do come around, dress to impress. If you don't own a slim-fitting black suit, invest in one now. Try Lanvin's ( jacket, GBP1,350, trousers, GBP410; mrporter.com ). Remember: Every man looks best in black and white. Throw a sophisticated tie, like Kris Van Assche's jacquard print ( GBP120; thecorner.com ), over a white Saint Laurent shirt ( GBP280; ysl.com ) for a touch of whimsy. Then put on your derbys ( Jimmy Choo, GBP495; mrporter.com ) and hit the town.

For the more frequent and more casual cocktail, tree-trimming, office and any-excuse-for-a-party parties, dressing down is encouraged. How down? Leave your suit and your sweatpants at home, and aim for that sweet spot of fashionably relaxed. When in doubt, stick to the classics. Pull on a pair of simple, slim-cut jeans like East Dane's 3x1s ( GBP188; eastdane.com ) or Frame Denim's Vinoodhs ( GBP235), with a crew-neck sweater ( Polo Ralph Lauren, GBP370), a white T-shirt ( James Perse, GBP45, all mrporter.com ) and white leather sneakers like Common Projects' Original Achilles ( GBP268; farfetch.com ). If you're going caroling, dress it up with a cozy overcoat, like Theory's wool version in camel ( GBP795; mrporter.com ). Even if you sing off key, no one will notice. Joy to the world, indeed.

Yale Breslin

Access Investor Kit for Ralph Lauren Corp.

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