A few things you should keep in mind: You'll want to save major hair color changes for the salon. The biggest DIY dyeing snafu is thinking you can transition from, say, black to platinum hair at home (or even from brown to blonde). Changes from one color family to another can require multiple processes, which are best left to a salon colorist who knows how to assess tones and minimize damage. “When dyeing your hair yourself, stay within two shades, lighter or darker, of your current color,” says Kari Hill, a celebrity colorist at Mèche Salon in Los Angeles. Remember that your result will be somewhere between your natural color and the photo on the box.