For skulls, cut half of dough into 8 slices; place on ungreased cookie sheet. Refrigerate remaining dough until ready to use. At lower third of each cookie, using fingers, create 8 skulls by slightly pressing 1/2 inch in sides of dough, forming jaw of each skull. Using end of wooden spoon, make openings in cookies for eyes and nose. Sprinkle with sugars. Bake as directed on package. Immediately form teeth in jawbone using tines of fork. If needed, make openings bigger for eyes and nose, using table knife. Remove cookies to cooling rack.