make it in a big circle the center color the tip of the corn then the secong color make a big circle around then add the third color as the outside then cut them up like you would a pie hope that helps
Are you using a cookie cutter in the shape of the candy corn? You could make your 3 colors of fondant. Then roll out strips of each one and lay them next to each other in the order you want. Then go and cut out the fondant with your cutter and put it on your cookie.