Be Your Own Colorist

It's easier than you think. Our mistake-proof guide shows you step-by-step how to pick the perfect shade and apply it like a pro.

Think inside the box
Before you hit the hair-color aisle of your local drugstore, ask yourself: How much of a commitment am I willing to make? Then, pick a formula based on your comfort level. Semi-­permanent dye is like a spring-break fling: It rinses away after about 10 shampoos, so you won't be left with any of those nasty telltale roots. Since semi-perms don't use peroxide or ammonia, they can't lighten your hair or give you a drastic color trans­formation. They only deposit pigment, enhancing or adding depth to your current shade.
Want something a bit more serious? Go with demi-permanent. It contains low levels of ammonia, so it will stay in your hair longer and fade out over about 25 washes. A demi can take you, at most, one shade lighter or two shades darker; it can also change your hair's tone--from, say, a medium brown to a medium auburn.
If you're ready to commit to a serious color change, you want a permanent option. These dyes alter your shade with peroxide and ammonia, so the color will last until it gets cut or grows out. These formulas give you the most versatility in how you can alter your color, enabling you to achieve more dramatic results.

Find the right hue
For the most natural effect, stay within three shades of your natural color. "When in doubt, start lighter," says Rita Hazan, owner of Rita Hazan Salon in New York City. "If the shade isn't right, it's easier to go darker than lighter." For a bigger change--say, going from chestnut brown to wheat blonde--see a pro.
Another thing to consider: undertones. Just like your skin, your hair's got them (they're either warm or cool), and the peroxide in hair color will expose them. "Brunettes tend to have warm undertones, which is why they're often surprised by how red their hair turns after coloring-­especially when going lighter," says Lisa Evans, a colorist at Salon Mario Russo in Boston. If you're worried about your hair looking brassy, choose a cooler, ashier tone.
Another trick for forecasting how your hair will react to hair color, according to Eva Scrivo, owner of Eva Scrivo Salon in New York City: Take a look at your grade-school pictures. If your hair was a warm, honey blonde in second grade, there's a good chance it'll go warmer when you color it now. And if you were a cooler, ash blonde or brunette, dying or bleaching will probably reveal those undertones. It's important to keep that in mind before you try out a new shade on your own.

Deep-condition
You wouldn't slap a coat of paint on a cracked wall, right? So don't even think about applying color without conditioning. "If your hair is damaged, the pigment won't adhere well to your strands and it will end up looking streaky," says Nicolas Cornuot, spa director of Phyto Universe in New York City. "So at least one week before coloring, pamper your hair with a deep-­conditioning treatment." Think of it as spackling holes before painting--you're creating an even surface for the color to attach to. Giving your strands a dose of intense hydration also helps protect them from the harsh chemicals used in coloring so you can avoid fried, crispy ends.
And don't shampoo for a day or two before you color. "Your hair's natural oils will protect your scalp and prevent irritation," says Nathaniel Hawkins, a hair stylist for Tresemme. Don't worry about any styling products that are left in your hair--they won't affect the coloring process. If you do wash the day of, lather up with a gentle formula; strong detergents can irritate your scalp. Mix that with the chemicals in dye and you could end up with itching and burning.

Do your prep work
Coloring your hair is kind of like baking a souffle: If you don't pay careful attention to every step, you'll likely end up with a big hot mess. "I often hear about women who dye their hair when they're exhausted, in a hurry, or have had a couple glasses of wine," Scrivo says. "That's when mistakes happen. Always concentrate and take your time."
Before you even rip open the box, "apply a thin layer of Vaseline along your hairline--from earlobe to earlobe and along your neckline--to prevent the dye from staining your skin," advises Harry Josh, celebrity colorist and a creative consultant for the John Frieda Collection.
Next, mist the ends of your hair with water. "Since the tips of your hair tend to be dry and damaged, they can soak up too much color," says Jason Backe, the color director for Clairol. "Some extra moisture will help color go on more evenly and prevent the ends from turning out darker than the roots."

Ready, set, color!
Pull out a comb and divide your hair into quadrants: Make one part down the middle and another from ear to ear, then clip each section securely in place. Apply the color one section at a time. "This is an organized approach to working with color that prevents any section of your hair from 'taking a holiday,' which is colorist-speak for 'you missed a spot,'" says Chuck Hezekiah, a color expert for Garnier Nutrisse. Apply color from the roots to the ends, working it through with your gloved hands. As soon as you've applied color to the last strand, start the timer--most color takes about 20 minutes to develop.
After dying, hold off on shampooing for three days. "This will give the cuticles--which open during the coloring process--time to close and seal in the color molecules," Scrivo says. And watch the water temperature when you wash: "Hot water can cause cuticles to expand and open, allowing some of the color to escape. The cooler the rinse, the better," says David Stanko, a color consultant for Redken.