Apply clarifying shampoo
You can apply clarifying shampoo on the hair. This will lighten or remove some of the colour. Remember to repeat applying clarifying shampoo if required.
Use Prell shampoo
You should apply Prell shampoo on your wrongly dyed hair. Let it stay on your hair for around 10 to 12 minutes and then rinse it. Repeat the process if necessary. Remember that Prell is used to remove the dyes from your hair. It is a detergent-type shampoo designed especially for striping colour from your hair.
Use dish detergent
You can use dish detergent in order to remove the colour of your hair. First form bubbles and then scrub your hair. Let it stay on your hair for around 10 to 12 minutes. In the end wash it with warm water. Remember that using powerful detergents will lighten dark dyed hair. In case you have good scalp conditions, you can even use laundry detergent.
Use virgin olive oil
You can apply extra hot virgin olive oil in order to lighten the colour of the dye used. Instead of using olive oil, you can even use other oil but warm them before applying.
Deepen the colour
In order to fix the wrongly dyed hair, you can deepen the colour with help of a semi-permanent colour. It should be much darker than what you have applied earlier. Remember to take advice by the manufacturer of the semi-permanent colour.
Re-dye if result is reddish hair
In case your hair colour is reddish, you need to re-dye your hair. This is because you did not apply the dye long enough.