Preheat the oven to 350 F. In a large bowl, mix together cake mix, eggs, and vegetable oil until smooth. Divide the dough between two bowls and mix blue food coloring into one and green in the other.
In a shallow dish, combine granulated sugar and ground cinnamon. Take a small amount of each cookie dough and roll together into balls. Roll in the cinnamon sugar mixture. Place the cookies onto a large ungreased baking sheet at least 2-inches apart. Bake for 10-12 minutes.