For this effect you will only need one picture that you will be transforming into a cartoon picture.
- Open your picture in Adobe Photoshop
- Make a duplicate of the picture
- Make the Foreground color black (which will make the lines Black) and the Background color whatever you want for the skin (in this case) to be
- Go to Filter > Filter Gallery
- Use the Sketch>Stamp Filter
- Using the Stamp option in the top left of the screen, adjust the Light/Dark Balance and the Smoothness to your likeness.
- Select the Background of your image and change de color so it is easy to distinguish the actual picture from the background
- DONE! you have your Barack Obama transformed into a cartoon character.