A really in-depth tutorial on how to create a nice abstract art style wallpaper.

Inspired from Summer Collection – Wallpaper by Benjigarner

Begin by representing the file that would have 1600×1200 px and 72 dpi. 

Choose after that the Rectangle Tool (U) to draw the background of the picture to be.

Select next parameters for the made layer by making a mouse click on this layer on the layers’ palette.
Blending Options>Gradient Overlay

Gradient’s parameters:

Use the last applied tool to draw this time a vertical stripe.

The layer’s parameters: Fill 0%
Blending Options>Gradient Overlay

Gradient’s parameters:

Blending Options>Stroke