Tutorial: How to create gradients with voronoi textures.

Recently, I created this image:

This is an image that uses a voronoi texture, and has a blue gradient overlaied over it.

Normally, mixing a voronoi texture with a gradient would not produce this. Here, I will show you how to make this.
 
First, add a plane to your scene. Scale it to fit the camera size. Then, UV unwrap it. (Apply the scale)

Now, add a material, and go to the node editor. Set it up like this:

Set the colours on the 2 colour ramps to be identical. Now, select the plane and enter edit mode. Subdivide the surface a few times, I would choose 100, but it depends on your plane's size.

Next, add a displace modifier. For the texture, set it to a new texture, and configure it as so:

Because the plane still looks so plain, lets change it up. Enter the Image Editor, and unlink any image loaded. Also, make sure you are in edit mode in the plane.

Now, select everything and rotate, scale and move it any way you want. You can view live updates in the viewport by going to the object tab and entering Shift + Z (Rendered viewport mode)

When you're done, add lamps, or set the world background colour to pure white.

You should be finished!

Here is what I have done in this tutorial, but with a bit of tweaking: