Dimensions. You have to know your dimensions. The bigger better.
Go to Deviantart.com and get grunge, homicide, and abstract brushes. If you know how to install them skip ahead to number two.
Open up your Library and go to this location - C:\Program Files\Adobe\Adobe Photoshop CS6\Presets\Brushes (If you installed it here otherwise find the CS6 folder and go to Presets\Brushes)
and extract your .abr files there (the brushes)
Open photoshop if you already haven't. I'm gonna go ahead and pick a decent sized picture. 520x320. Gives us enough room to work with.
Go ahead and make the first layer black or a dark color. After that create a new layer. That's where the design will start.
Pick a grunge brush but make sure it's small. For this one, spread the brush around not too much but not too far. It doesn't have to look perfect, the following layers will make it look a bunch better. The grunge you pick may come with symbols and you can use them.
Mines not too far apart or too close together. Leaves enough room for the black and blue to be seen.
Once again make a new layer. This time we're gonna use a darker color. Pick a abstract brush, but be weary of where you put it. This will be the main effect of the design. Feel free to use multiple different abstract brushes here.
It's almost over, all you have left is the homicide brush and option text and/or borders. This is going to be the lightest color on your design. Make another layer again. Pick the homicide brush and put it where it's the most boring part of the picture. (plain)
That's the finished product. Optionally you can add a border and other effects.
I'll add the .psd in the attachments if you would like to alter it.
If you think you can do better, post your image so I can see it.
A thanks and +rep would be nice.