Have you tallied up the number of celebrities going from blonde to brunette lately? Naomi Watts made the switch for her biopic portrayal of the late Princess Diana during her undercover days; Lana Del Rey debuted an espresso mane at the 2012 GQ Men of the Year Awards (she was voted Woman of the Year by the magazine); and Jennifer Lawrence recently changed back into chestnut strands. Brunette was also the color du jour on the 2012 fall runways, with Guido Palau even transforming three flaxen-haired models to brown-haired beauties at Calvin Klein Collection.
Blondes might have all the fun, but the sudden shift proves that there is something intriguing about going darker. The latest romance with the hue can be credited to Rooney Mara, who put the deeper shade firmly back on the radar with her red-carpet appearances for The Girl With the Dragon Tattoo. A shift in taste can also be a factor. According to a 2012 hair color census presented by L’Oréal Healthy Look Crème Gloss Color, 75 percent of the survey’s respondents said that brunettes are the most trustworthy and 64 percent said their best friend has brown hair. Eight out of ten respondents thought that brunette guys are the most attractive.
If you're thinking about making the switch or just want to make sure your brown locks are looking their best, here is our expert guide to becoming a brunette bombshell.
Picking Your Shade
The best way to choose the most natural shade of brown is to take a look at your skin tone. Those with lighter skin tones and pink undertones look best in cool medium-brown and reddish-brown shades. Women with medium skin tones and yellow undertones also look great with medium-brown strands, but can experiment with a wider range of warm colors from caramels to mahoganies. Dark-skinned women with olive undertones can most successfully carry dark-brown and dark-reddish-brown locks. Of course runway and celebrity colorists have been pushing the limits on these rules, pairing alabaster complexions with near-raven hues and dark complexions with lighter shades of brunette. It just depends on how severe you want your brunette shade to appear.
Adding Dimension 
If you want to add dimension to brunette strands without sacrificing richness, don't immediately think about highlighting. Instead consider "flipping the script," says Redken hair color consultant David Stanko. Get lowlights that are one shade deeper than your natural or chosen brunette hue.
Another way to boost depth is to balayage (freely paint on) a brighter, bolder color to pieces of hair around the face, says Oscar Blandi Salon colorist Amy Mrkulic. "Balayage gives brunettes a very natural and soft look," she says. "It's a maintenance-free way of adding contrast to a brunette who might be afraid of highlights altogether."
If you do decide to go with highlights, just add a few delicate ones to strategically frame your face. Instead of using one shade to lighten, use a few different shades—such as golds, reds or chestnuts that are also within the same family of the base color and don't compete with your skin tone and eye hue—to create a tone-on-tone result. “And never go too close to the roots,” Stanko says. “You want your lightened pieces to look like they were lightened by the sun."
Glossing It Over
Brunette strands look their healthiest with intense shine. You can achieve this on a day-by-day basis at home by keeping your hair in great condition and turning to gloss-fostering masks, serums or hair oils, such as Shu Uemura Full Shimmer Illuminating Treatment MasqueRedken Color Extend Shine Enrich, Garnier Fructis Style Brilliantine Shine Glossing Spray and Kérastase Elixir Ultime.
Or you can turn to glazes that are to hair like a clear top coat is to your manicure. Oscar Blandi At Home Salon Glaze provides a built-in treatment that hydrates hair while boosting shine. To get a professional boost, get an in-salon glaze, like Redken Shades EQ Demi-Permanent Color in Crystal Clear. It doesn't change your color; it simply adds shine, health and body. “Usually brunettes fade to auburn, and not all of them like that," Stanko says. "So a glaze helps to cool off those unwanted brassy tones.”
Glaze can also be used to add pigment, for those who are not quite ready to dye locks. "A colored glaze will add richness, depth, shine and volume to your hair without the chemicals and will wash out in three to four weeks depending on how often you shampoo your hair," Mrkulic says. John Frieda Brilliant Brunette Liquid Shine Luminous Color Glaze imparts a touch of glossy brown color and a multidimensional satiny texture and can be applied in your shower after shampooing and conditioning.
Playing It Safe
The key to maintaining your new brown hair's richness and depth and preventing it from fading or changing colors too quickly is to use shampoo and conditioner that are safe for color-treated strands. Kérastase Chroma Sensitive Cleansing Balm, for example, is sulfate-free and will help the color stay vibrant longer. Another pro secret: If you're going to be outdoors on a sunny day for an extended period of time, coat your hair with a heavy moisturizing mask to shield it from damaging UV rays. Finally, stock up on heat protectants, which act as a barrier between your hair color and your styling tools. Try: Redken Duo Shield 07.

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