This is only really necessary if you are going for a specific shade, or if this is your first time dyeing your hair with food coloring. Take a strand of hair from an inconspicuous area, and rinse it. If the color is too light, leave the dye on longer. If it just right, move on to the next step. This will seal the hair's cuticle and preserve the color. You can do this over the sink or in the shower. Don't use shampoo and conditioner, however, or it will remove the color. If you dyed your hair multiple colors, keep the dyed sections separate. You can also towel dry your hair then let it air dry. Make sure that you use an old towel, however, as some of the dye may rub off. If you used conditioner, avoid washing your hair for 3 to 5 days. This will help the color set. It would also be a good idea to sleep on colored (preferably dark) pillow cases to avoid staining.  Temporary dye jobs will start to fade with each wash. They should last about 2 weeks total, depending on the color and your hair type. Some dye jobs may come out after only 2 to 3 washes.  Permanent dye jobs will last about 3 weeks before they start to fade.
एक स्ट्रेंड रिंज टेस्ट (strand rinse test) करने के बारे में सोचें: डाइ को ठंडे पानी से धो लें: अपने बालों को लो सेटिंग पर (low setting) ब्लो-डाइ करें: अपने डाइ किए बालों का ख्याल रखें: