After dying my hair 'dark brown' a few months ago, it turned black and since then any dye i put on top of it just turns it black again! Does anyone know how Demi dye her hair black to the colour in this picture, or have any idea how I could get that kind of colour from black??:

http://images.wikia.com/sonnywithachance/images/1/18/Easiermoney.jpg