Frost cake with thin layer of frosting to seal in crumbs. Refrigerate or freeze 30 to 60 minutes to set frosting. Spread remaining frosting evenly over cake. Let frosting set a few minutes. Carefully cover with paper towel and gently pat to give frosting a textured appearance; remove towel. Outline scales, legs, mouth, nose and eye with black gel. Decorate with green gel and jelly bean eye. Store loosely covered.