I think that any time you are given a choice of making a cake around someone's job or their hobby, you should always choose the hobby. That's just my humble opinion. That being said, I made a 50th birthday cake for a golfer. That's right...hobby.
First, stack two layers of cake.
Then cut a divot out of the top edge and flipped it over to make a hill. So with conserving all of the cake you get a nice contoured golf course. At least it will look like a golf course in a minute.
Add a little crumb coat.
Frost the whole cake with grass green.
Spread a little light green for the putting green and a little light brown for the sand trap.