While playing Yaris you will notice that in the lower right hand side you will see kind of like a globe in a circle with a number below it. In that circle the number is how many coins you have collected in that one level (not total). Once you reach a total of 1,000 coins (across all games) you will unlock this achievement. To check your current total number of coins, go to the main menu, then click on "single player", in the top right hand corner it will say "Coins: (x amount of coins here)". It only took me one level, so you'll have it for sure at the end of your third if your really not that good at this game.