GETTING HAIR DYE AT THE STORE
Check for an expiration date
Some hair color boxes are stamped with a sell-by date, but others give away their age only by the amount of dust they accrue. If a kit is (or appears to be) past its prime, opt for a new one. “Color oxidizes over time, meaning the pigments may have already started to develop,” says Carlos Rodriguez, senior colorist at Sally Hershberger Salon in Los Angeles.
Stay within your range
When it comes to single-process color (one shade applied to your whole head), don’t veer more than two shades lighter or darker than your natural hue, advises Rodriguez. In doubt? Choose the less dramatic option—it will be easier to correct if you’re unsatisfied with the results.
Know how to decode dyes
Want a long-lasting effect? Opt for a permanent formula; thanks to the combination of ammonia and peroxide, it completely alters your tone and lasts until your hair grows out. Typically labeled as ammonia- free, demi-permanent tints contain low levels of peroxide, helping to enhance and brighten your natural shade; results last up to 30 shampoos. For a more temporary fix, try a semipermanent formula, which coats strands with pigment that fades after six to 12 washes.
Target silver strands
For minimal graying, use a demi-permanent formula in a neutral or ash tone that enhances your natural hue, says Rachel Bodt, a senior colorist at Cutler salon in NYC. (The shade names listed on the box will help you find the right tonality.) If your mane is more than 50 percent gray, use two boxes of permanent dye from the same color range—one warm, one neutral—and mix together equal parts before adding the developer.
“You might not use both boxes, but keeping an extra hair color kit on hand ensures you’ll have ample coverage for tresses that are super-thick or long,” says Erin DeVincenzo, director of consumer affairs for Garnier. “The spare one could even serve as a backup if you accidentally spoil or spill the first batch.”