Have a Plan
"Standing in front of that wall of color at the drugstore can be deeply confusing, so consider what your goal is before you get there," says Brad Johns, artistic director of Avon Salon & Spa in New York City and Clairol global creative color director. "Do you want to lighten up? Cover gray? How long do you want the color to last? These questions narrow the field immediately."

Consult a Pro
You don't have to pay salon prices to benefit from professional expertise—most salons offer free color advice. "A consultation is a great way to find out which shades will work best with your skin tone or which ones will be the most high maintenance," says New York City colorist Renée Patronik. If you're uncomfortable going in only for a consultation (knowing you don't intend to return), ask your regular stylist for guidance.

Read Product Descriptions
Don't be taken by those golden blonde Veronica Lake waves on the front of the boxes. "The pictures are alluring, but the chart on the side is the reality—that's what tells you what shade you'll actually get to from the color you are now," says Johns.

Stay Within Range
We can't say it enough: Many colorists advise against straying more than two shades from your natural color, even in the salon; definitely don't attempt it in your bathroom.

Take the Strand Test
We can't say it enough: Many colorists advise against straying more than two shades from your natural color, even in the salon; definitely don't attempt it in your bathroom.

Step Out of Shadows
You probably appreciate how generous your soft bathroom lighting is to your skin. Bright natural light, however, is best for judging haircolor, so after the strand test, assess your results near a window.

Dye Regrowth
Recolor your whole head every six weeks and your hair will soon feel like straw. Instead, apply dye just to the regrowth and then smooth it over the previously colored hair a few minutes before the processing time is up. Between dye jobs, Clairol Nice 'n Easy Root Touch-Up kit ($7) camouflages roots in ten minutes with a dye formulated to mimic the way color fades, so it matches the rest of your hair.

Have No Fear of At-Home Highlights
Those complicated caps and hooks have been revamped to give you much more control over your hair's destiny. Clairol Herbal Essences HighLights ($10) includes a two-pronged comb that can be filled with the lightening formula, so you're always using the right amount. L'Oréal Hi-Light Styliste ($11) offers both a mascara-like wand, to create thin streaks, and a brush, for broader strokes. The pros recommend spacing highlights about one and a half inches apart and brushing the bleach on both sides of the hair from roots to ends.

Don't Skip Conditioning
Most kits these days come with extra conditioning products. Use them. All Clairol Nice 'n Easy colors, for example, include ColorSeal Gloss, which locks in color with resins and silicones. "Put it on for about two minutes after the color, and then keep using it once a week," says Johns. "It also makes the hair really shiny—my assistants at the salon are always asking me for extras."

Consider Toner
For color that starts to get brassy after a few weeks, L'Oréal now has an at-home toner (L'Oréal Tone Refiner, $9) that neutralizes that yellowy tint while adding luster to the hair. "It's a no-brainer," says Patronik. "It takes six minutes, and you can't mess it up."

Don't Make the Same Mistake Twice
"If you don't get the color you want, call the hotline listed on the box or go to the salon—don't run out and buy another color," says Johns. "After two mistakes, we're all sunk—even hotline operators and professional colorists. Your hair is so saturated that it will need a corrective color process, which can involve stripping the old dye off—and starts at $300."