If you've played this challenge before then you can select it from the practice menu, if not then you'll have to wait for it to come up during a game.
The game involves you hitting 'A' a few times as quickly as possible then it will give you 2 buttons to hit alternatly to shake your character which will make him burp. This will push your toy boat towards the finish line. Your boat must cross the finish line for this achievement.
You can make things easier if you plug in 1, 2 or 3 extra controllers to remove the AI opponents.