As we all know, black hair dye is a special case.  A permanent black hair dye is very hard to remove from your hair completely so you should consider some precautions before applying black hair dye.  For your hair, you have to bleach it but bleaching with chemicals can really damage your hair like making it stretchy and thin.  The worst is it may totally weaken your hair and lead to hair breakage. 

Sometimes we cannot avoid staining our skin with black hair dye.  The best thing to do to prevent it from staining is to apply Vaseline around the hairline before dyeing and also extra care should be observed when applying hair dye.  Cigarette ash can also remove hair dye stain by rubbing it to the stained skin.  You can also try using cotton balls dipped in milk and rub vigorously over the stained part. Even nail polish or hair spray can be a good agent in removing hair dye stains. 

It is really hard to remove hair dye when it gets on places you do not want it like on your carpet or clothes.  Using detergent and water is a good way of removing black hair dye if it stains in fabric.  There are also commercial products that help get rid of dye from your hair, skin, clothes and carpets. There are products that can remove and correct your hair colour.  You can also use gel that will help cleanse your skin and scalp. 

There are also some home remedies in removing black hair stains like hot oil treatments, shampoo and constant exposure to water that can eventually fade hair dye.