Do it Yourself: Creating the Image
What I find neat about stenciling is how realistically it can capture the essense of an image with only a couple fields of color. So with that being said, I'll be going over how to convert photographs into stencils (Though drawing stencils by hand is a perfectly viable option too).
First select your subject. I'll be using LeBron James, Miami Heat basketball player, as mine. Take a photo of your subject and open it in Adobe Photoshop, where you can then remove the background from the image. I used the magnetic lasso and then quick mask mode to do this.
Now that you have a clean white background, you'll want to convert the image into black and white or gray scale. I used the live trace feature in Adobe InDesign to convert the photo into a black and white vector image. Using gray scale allows for multiple layers of color, but we'll stick with bkack and white to keep things simple.
The image may seem like it's stencil-ready, but hold your horses; there's one more important step.
Go through and make sure there aren't any "islands" of white in the image. This would equate to a piece that isn't attached anywhere and essentially sits freely from the rest of the stencil. Be sure to connect white "islands", which I had to do with the letters in "HEAT."