One clever way to make your hair multi-tonal is to dye different layers in different shades.
You don't have to go so lurid with your choice of hue. Loud mouth Nicki Minaj isn't afraid of some neon colour but this colour layering will look really stunning if you use shades that are just a few depths apart in intensity to really add some movement and interest to your hair.
1. Split the hair in to three horizontal sections - leaving you with a top, middle and underneath layer.
2. Apply a different shade to each layer or keep it strikingly simple with just two contrasting colour layers.