I ended up using this tutorial to make my Andy Warhol Pop Art picture: http://www.ehow.com/how_5348870_make-pop-art-using-photoshop.html
This is my original photo:
And here is the finished product:
If you choose to try this, use a picture with a more simple background – it took forever to delete all the little flowers! Also, I painted in some thin lines to close off the face and hairline so that I could use the paint bucket tool to fill the areas in. The best part about this project was colouring in the pictures!