This game is really easy to play. All you need to do is press the swim button and win the race by collecting coins, more you play more coins you can collect.
You may choose the character before you start the race. While improving the levels your stamina levels will go down, all you need to do is increase the stamina levels by buying stamina.
When you do have 50 coins you can buy the stamina, and continue to race.
For stunts, you need to swipe your finger to do the stunts. Grab the point and do the stunts.