Mix 3 drops each blue and yellow Neon Food Color into frosting; set aside.
Shake coconut in large plastic bag with 6 drops each blue and yellow Neon Food Color until well coated.
Cover cakes with green frosting. Sprinkle with green coconut to create a grass-like finish.
To make "tombstones", place chocolate frosting in small plastic bag. Snip off a tiny corner of the bag. Squeeze out the letters "RIP" onto each cookie. Place cookie into one end of each cake. Arrange cakes on serving platter to create a graveyard. If desired, surround with crushed cookies to make dirt