It also enables the colorist to get a light, wheaty color minus any red, a common problem for brunettes gone blond." — Joel Warren Q. If I condition every day and use moisturizing products designed for color-treated hair, do I also need to deep-condition?A. "The bigger the color change or the more complicated the color, the more maintenance is required. Most women think maintenance refers to the frequency of touchups, not the aftercare. A deep-conditioning mask once or twice a week is essential — but it takes no more than three to five minutes, thanks to higher percentages of emollient ingredients like shea butter and botanical oils. A mask right before you color is key: You want the cuticle in great shape before any chemicals are applied." (Try Bumble and Bumble Damage Therapy Masque, $10; Phyocitrus Mask, $32.) — Brian KellerQ. Will the new wet-to-dry flat iron damage my hair more than blow-drying followed by flat-ironing?A. "Both styling methods are damaging if used too frequently and aggressively. Always shield your color with a protective silicone spray before heat styling, and use the lowest temperature setting. Frankly, I’d rather you blow-dry and then briefly flat-iron if you must, lightly and quickly running the iron over spots that need extra smoothing." — Brad JohnsQ. I swim to stay fit, but it’s turning my hair green. What do I do?A. "Nothing works a hundred percent — water seeps in even under a bathing cap — but there are several pre-swim treatments that slow penetration of the chemicals in the water. Kerastase Soleil Huile Genereuse spray ($29), an oil that gives hair a sleek, shiny look, is very effective as a preventative in the water. Follow up with a shampoo and conditioner that remove copper residue from pool water. Otherwise it can remain in cracked cuticles, giving blond hair a greenish tinge." (Try California Baby Swimmer’s Defense Shampoo, $10.) — Beth MinardiQ. I hate my new hair color. How long must I wait to recolor?A. "If you really hate it, you can go back in 48 hours. Let your scalp and hair settle for a day to give the cuticles a chance to lie flat. Then deep condition before you go to the salon. Use a very rich product with shea butter, and leave it on as long as you can." — Brad Johns Q. After years of highlights, I’ve morphed into solid blond. How can I regain contrast without going darker?A. "Lowlights on the under layers can provide you with enough contrast so the color regains a more natural look. Or start over. Color the whole head with a semipermanent dark blond (which will also add shine), then add subtle highlights. Resist highlighting every time you go for a touchup — that’s how you wind up with a whole head of highlights. Three or four times a year will maintain a multitonal look." — Brad JohnsQ. Roots are supposed to need a touchup every four to six weeks, but mine show up two weeks after I color. Should I touch them up then?A. "Do a mini touchup. Just put color around your hairline and one inch on either side of your part. This technique also works if you love your natural color and only want to color the gray at your temples. Use a Q-tip to get just the strands you want. Don’t apply color all over every time you color, either. Slick conditioner on the ends while the color is cooking at the roots, then refresh the ends by working the color through them (right over the conditioner) for the last five minutes." — Louis LicariQ. My brows have some gray in them, but I’m blonder than ever. What color should brows be? The same color as my hair? Darker? A. "I have a pet peeve: Marcia Cross’ matching red brows on Desperate Housewives. Brows should be softer in tone — never too blond, because they disappear, exaggerating lines around the eyes. Brunette brows shouldn’t be too dark, as they give the face a severe look. And redheads always look better with browner brows." — Beth MinardiQ. Are color-enhancing shampoos and conditioners really any good to prevent fading between appointments? How can I be sure they won’t change my color?A. "These products brighten like a glaze, and some do deposit a tiny bit of color, but they don’t have enough power to change it. I recommend mixing a bit of color-enhancing shampoo with your everyday shampoo each time you wash your hair.