We will create abstract art wallpaper in easy steps. Create a new file having
1024x768 px and
72 dpi. The next instrument

will be helpful in representing the primary background of the picture we want to create next.
Blending Options-Gradient Overlay
Gradient’s parameters: 
Take the here shown instrument

and draw a circle of white color.
Fill 36% on the layers.
Select this tool

and try to draw a kind of sun rays coming out of the circle. All of them should have the white color.