Dark colored acrylic paint
Sharp pointed tool (I used a tool that came with a previous scratch art kit that I had done. But anything works.)
Step 1: Coat the CD with black acrylic paint. Make sure you are painting on the side that casts rainbows when you look at it from different angles. As I said, I didn't read the tutorial, so I used tempera paint (which I had a lot of), and that didn't work out too well. But we learn from our mistakes :)
Step 2: After letting it dry, carefully trace out your design on the cd, making sure not to peel the paint away. The picture shown here shows my original design, but I decided to do something simpler in the end.
Step 3: Carefully scratch away the paint to create your design. Easy as 1, 2, 3! :)
And there you have it!