This one is pretty simple. You need to play a full 18 hole CUSTOM game for this to unlock.
Your performance doesn't matter, so you can play as you like, but there is a quick way to get this achievement.
* Choose OFFLINE from the main menu (means there's no waiting for others to take shots)
* Choose "COURSE: ANY" (I chose twilight)
* Highlight MODE, and press
to bring up the game settings.
* Press
on any mode on the left (I chose Classic), then modify the settings on the right. (any settings, just make them different to default)
* Press
to apply these changes. You can tell your game is custom because the mode will say "Classic (Custom)", or whatever type you chose.
* Then press
to start the game
* When ready to take your first shot, press
and choose "FORFEIT HOLE" (this will instantly end the hole)
* Repeat for all 18 holes
Should take 5 minutes for this achievement this way.
NOTE: on the main menu, there is an
"customise" option. This is custom ball settings, not the custom match settings needed for this achievement.