Bake a 9x13 cake. Use food color to dye your icing grass green and a small amount dyed black for the lettering and ramp. I iced the cake green putting a big glob in one corner. Then I used the black icing to run a strip down the blob and along the cake to make the ramp. Then I used a grass tip (has a bunch of holes in the tip) and placed the grass around the cake and along the ramp. I bought a cake box and a gold cake board.
I also bought a set of Tech Deck skate boards and put them on the cake ran a green border. Wrote on it and viola!
He loved it. But of course, you can never get a serious picture of him.
If you click on the picture of the cake you can see the details close up.