it depends on whether or not it is permanent, and whether or not you are a blond. If it doesn't come out in 1 month, you will have to shave your head.
Yes but you really shouldn't be adding more and more color to your hair. Also be sure that black is the color you want for a long time. It will not come out easily or with out damage.
Yes but henna stays in a really long time and will not come out if you change your mind.
It depends on the manufacturer of the color, if it's professional color the directions are inside the box the color came in, but usually it's equal parts color to developer, but again it depends on the color.
It depends on what kind of hair color you have, and how long you leave the hair die in. If you follow the instructions it should come out great.
if you want to keep you hair color wash you hair with soap
Depends on the color you want. The dye should have come with instructions to indicate what shade it will come out dependent on how long you had it on. It usually gets darker the longer it is in.
same procedure as you would with long hair.
In general, the hardness of municipal water has little effect on the color of hair dye or on how long it lasts.
The color will fade slightly, but permanent hair color will stay in your hair until it grows out or you strip it.. Roughly 6-8 weeks depending.
That same day.
How long Garnier Fructis Color lasts on ones hair depends on how often the hair is washed. If hair is washed every day the Garnier Fructis Color will start to fade in a few weeks. If a person washes their hair less, the color could last up to three months.
Hair color is an inherited trait, although it is also a trait that can be altered, by artificial means, and hair color also varies with age. Eventually, if you live long enough your hair will turn white, regardless of what color you inherited.