To start you need:
~ a white t-shirt (see my paragraph about t-shirts here)
~ 2 buttons
~ black fabric
~ orange fabric
~ heat'n bond iron-on interfacing
I couldn't find any by-the-yard orange fabric I liked so I went with a very cute fabric quarter. As it turned out, the thin cardboard from the fabric quarter was perfect to make a pattern (see above).
I'm not totally in love with the buttons - I wish they were a tad bigger - but they will do. It looks like the original shirt was made using a button kit and fabric.
I used different things I had laying around the house to trace for the mouth circles.
The size circles you want to use will depend on the size shirt you're using.
I definitely recommend using heat 'n bond! Simply iron it to the nose and mouth pieces, peel the paper off, figure out where you want the pieces on the shirt, then ironing those pieces to the shirt. Once it's all bonded use a zigzag stitch to further secure everything. I even used the zigzag stitch to attach the button eyes.
That's it. It's an extremely quick and easy project.