The color wheel turns again as designers go in for daring juxtapositions of rich, sophisticated hues like violet and saffron (blouse, Club Monaco, $119; skirt, J.Crew, $78). To make a mix like this work, use tones that are the same level of intensity; it also helps to separate them (grosgrain ribbon worn as belt, Mokuba). The one-bare-shoulder look highlights a part of the anatomy that's slow to age (hooray!). Kara DioGuardi, who needs interesting tops as a judge for Fox's iconic music show American Idol—she's mostly seen from the waist up—says this style makes her feel "sexy but still strong." Edgy quartz, onyx, and sapphire jewelry (Iradj Moini) and glittery-strapped nude shoes (Lanvin) give this Grammy-nominated composer (for everyone from Gwen Stefani to Celine Dion) a touch of rocker chic.