If you are a blonde and want to go for darker color like brown, then the application of a color containing ammonia and peroxide can create the desired color base on the hair. If you want a lighter shade, like from black to brown, then an additional step is required. First of all, bleach is used to strip the existing color from the hair and after that, the application of color due to interaction of ammonia and peroxide creates the lighter shade.
Choosing a hair color is not a simple job and it requires a great deal of thought process. You should choose it after analyzing the color of your hair, eye and skin. This will narrow down the choice of your hair color. Most hair colors fall in the category of either cool or warm families. You are warm skin type if you have brown or dark eyes and olive, dark or golden skin, and you are cool if you have blue and green eyes and fair skin. People with warm skin can go for golden shades and those with cool skin may go for ash blonde and cool brown.
To dye gray hair can be difficult because of its tough texture. Lighter shades of semi-permanent hair color can be used if you have gray hair less than 15%. Light shade will blend perfectly with it. If you have more of gray hair, you can use the ashy permanent color because it will give blonde effect to the hair.
To prevent any hair color disaster it is always recommended that you perform strand test before its application. By this you may get the idea of the color that will come out on your hair. If you are not satisfied by the color of the test, you can opt for another color. But, if you realize after applying the hair color that you are not satisfied with the final outcome of the color, you should always visit a saloon where they will use color-removing product and you will find yourself back with your original hair color.