Write an article based on this "Choose between a permanent, semi-permanent, or demi-permanent dye. Go with a dye 2 to 3 shades lighter or darker than your current color. Leave your hair unwashed for 2 days before you dye it. Wear an old button-front shirt or robe to avoid stains. Test dye on a small section of your hair before dyeing the rest. Rinse and dry your test strands to check the color."
Permanent dye will last the longest and can cover gray hairs and roots. Semi-permanent dye can only darken hair, and will last up to 8 washes. Demi-permanent dye can slightly lift your hair color, and will last up to 25 washes.  If you’re using permanent dye, apply it to your hair when it’s dry. For semi-permanent dye, shampoo your hair and dye it while it’s still slightly damp. When deciding between 2 colors, stick with the color that is closer to your natural color. Making a big change, like bleaching dark hair, is best done with a professional salon colorist. If your hair is longer than shoulder-length, buy at least 2 boxes of dye in case you run out during the process. You should only need 1 box if your hair is shoulder-length or shorter. Your scalp will have built up enough natural oils to protect your skin from irritation. Washing your hair removes those natural oils, so it’s best to wait 2 days before dyeing. If you pick an old shirt or robe that closes in the front, you won’t have to lift anything over your head when it’s time to rinse out your dye. You can also wrap an old towel around your shoulders and fasten the ends together for an extra layer of protection.  You can also lay down newspaper or garbage bags to protect floors and surfaces from dye stains.  Work in a room with natural light if possible, so you can accurately check your new hair color.  The bathroom is generally the best place to work, especially if you have a window that lets in natural light. You can use the mirror to check up on your progress, use the countertops as a workspace, and the sink and shower are readily available in case you need to rinse off. If your dye doesn’t have instructions for a strand test, mix 1 teaspoon (4.9 mL) of color and 1.5 teaspoons (7.4 mL) of developing cream. Using disposable gloves, apply the dye to a 1 inch (2.5 cm) section of your hair.  Not all kits have the same mixing ratio (for example, some might require a 1:1 mixture of color and developing cream for the strand test), so check the instructions before you start mixing the dye. If you’ve dyed your hair before, work the dye from root to tip, taking care not to get dye on your scalp. After the instructed time has passed, which is usually 20 to 30 minutes, rinse your test strands with lukewarm water. Dry it with a blow dryer, and then check the color. If you’re happy with it, you’re ready to dye the rest of your hair. If you’re not happy with your test strand’s color, you can try a new color on a different strand of hair.