Read the answers from webmd to those and other frequently asked questions about hair coloring.
37+ Hair Dye Over Blue
Pictures. If you want to stick with bright colors like your blue. You can always go to a salon to correct place a bath towel around your shoulders that you don't really care about (the shampoo and dye will run and could potentially get on your towel).
Howto Red To Navy Blue Hair Youtube from i.ytimg.com
To learn more about changing colours, have a look at colour theory for hair dyeing. You can also lighten it or darken it using lighter or darker shades to get a different color than blue. The cool shades will enhance the cool base of your skin tone.
But i am planning to dye it blue;
Put hair dye, over hair dye? You probably have indigo dyed cloth in your closet, in a pair of blue jeans. Not if you are looking to come out with rainbow hair. Of course you can, and i'll tell you which colors are the best for doing it.
