Day-to-Night Accessory Guide

Mary Alice takes a pair of modern slim jeans out for a night on the town. "If you don't want to or can't wear the skinny, go for the slim or go for a straight cut," she says. "And the good news out there with denim from Banana Republic, [Ann Taylor] Loft, Gap, is it's all got spandex in it now."

If you've got curves, Mary Alice says ankle boots can balance out your figure. "It really does give a better proportion," she says. "You've just got to try it on and make sure."

Another effortless way to dress up a pair of jeans is to throw an embellished T-shirt under a cashmere sweater or a shrunken jacket. "It's a quick, easy way to add a little glamour under all those classics you already have," she says.

Jacket: Rachel by Rachel Roy bouclé jacket, Macy's; embellished shirt: Rachel by Rachel Roy, Macy's;boots: Rock & Republic Leena, Zappos.com; ring: Rachel by Rachel Roy, Macy's; purse: Michael Kors, Macy's