If you're thinking about coloring your hair, red is a feisty and tempting choice. But there are a few things you should know, whether you're going for a Nicole Kidman strawberry blond or a Rihanna red. Less than 4 percent of the world's population has naturally red hair. If you want to get the look, then it's best to leave things to a professional, who can recommend the right hue for your skin tone and coloring. If you want to do it yourself at home, then many of the popular brands of color can help you choose the right color for you. Try Loreal.com's "Can I help you?" tool, which will ask you questions about your coloring and style to match you with the best color and formula. There are other tools that allow you to "try on" color by uploading a picture of yourself and choosing different colors and hairstyles. But your natural color may vary, depending on the light and the picture you use, and colors online aren't always true in real life. Staying within two shades of your natural color is the best way to get natural-looking color. And if you want to ease into red, then highlights are the way to go.