Step 1 - Find a picture
OK, this is the first step. Find a picture that you would like to use. I found this picture on google you can use it if you choose to. Jessica Simpson
Ok after you've got the picture, your going to open it in photoshop. Once you've done that were going to grab the burn tool. Change the exposure setting to about 34 and use a 9 pixel size brush. With this your going to shade out through the eyes make them dark. See what I did.
Step 2 - OK now next step
Keep working around the eyes. Anywhere that you see shading on the pictures face at the burn on it. Make other areas darker other lighter. See what I'm doing just using the burn tool and overlapping.
Step 3 - New Brush
Now your going to grab a new brush. A bigger one about 40 pixels. Now go over the whole face and make it darker. Don't concentrate too much in one area, spread the brushing out and try and cover it all equally.
Step 4 - Adding Texture
Find a image on google free for personal use.
OK now copy this picture and place it over the image. Maybe under the eye or where ever you want the effect to be. After you've done that go to layer/layer style/blending options and put it on color burn. Then it should blend in nicely. You can copy this and put it on several spots. So it looks like a crack on the face.
Step 5 - Duplicating
Ok, now go back on the picture of Jessica Simpson. Your going to duplicate this and put it on top of all other layers. Now your going to move it about 10 pixels to the right. You can do this by pressing the arrow keys. After you've done that, your going to cut out squares in the face. You can do this by using the rectangular marquee tool. Make selections and press backspace to cut them.
Step 6 - Go Back in Time
Ok, now go back to the first Jessica Simpson picture that's all the way on the bottom. Copy it and place it on top. Now move the picture 15 pixels to the left. Cut out again and see what you get. There you have it, your final weird looking wallpaper. Good luck with your results.