Once you have repaired the hovercraft at the Mamago garage (beginning of the game), head to the city and in the pedestrian district. Once there, enter in the Akuda bar and find Peepers on the upper floor. He'll challenge you to a very simple game: a ball is hidden in one out of 3 coconut shells.
To make things real easy, bet 50 credits so his moves will be slower. Keep your eyes on the coconut shell under which the ball is at the beginning (middle one) and select it once Peepers is done switching them.
Repeat 2 more times and the achievement is yours.
This can be done at any time in the game (except at the very end, once you can't go back to explore the world).