To prolong your color and make it look more vibrant, you can use a vinegar rinse made up of equal parts water and white vinegar. Pour one cup of white vinegar and one cup of water into a medium sized bowl. Then, pour the solution over your hair. Leave it in for about two minutes and then rinse well. You may want to shampoo and condition your hair again after doing a vinegar rinse to remove the smell of the vinegar from your hair. The less often you wash your hair, the longer your hair color will last. If possible, try to wash your hair no more than twice per week. To keep your hair looking clean between washes, you can use a dry shampoo.  When you do wash your hair, make sure that you only use cool or lukewarm water to wash it. It is also helpful to follow up your conditioner with a blast of very cool water to close the hair shaft and lock in more of the color. Heat can cause the color to bleed from your hair and this may cause your hair color to fade faster.  To prevent this, try to avoid using any heat treatments, such as blow dryers, flat irons, or hot rollers.  If you need to dry your hair, make sure that you use the cool or warm setting on your blow dryer rather than the hot setting. If you want to curl your hair, then try putting foam rollers in before you go to bed. These will curl your hair without the use of heat. Most blue dyes are semi-permanent colors and these dyes tend to fade fast, so you might notice your color fading a little over time. To maintain your vibrant blue color, you will need to re-dye your hair about once every three to four weeks.
استخدمي الخل لغسل الشعر مباشرةً بعد صبغه. اغسلي شعرك أقل من المعتاد. ابتعدي عن الأدوات الحرارية لتصفيف الشعر. أعيدي صبغ شعرك كل 3 أو 4 أسابيع.