This tutorial shows how to make a regular picture look like this:

Cool, huh? Well, here's how you do it.
Pick the image you want to use. I used this one:

Open up Photoshop Pro CS2. Change the attributes and stuff like this:

Once you've done that, paste (ctrl+v) and go up to the top bar. Click LAYER>>NEW FILL LAYER>>SOLID COLOR. Now, pick a color. I would suggest using white. All you should see now is white, right? Go over to the side bar and click the History Brush:

Now, press and hold the left mouse button, and move the brush this way and that. If it doesn't work, then exit out of the document, do it all over again, but click LAYER>>NEW LAYER. Then do the fill layer.
After you've done that, save it as a PNG, and you've finished! I hoped this tutorial helped!
~Mariah