How to get Coins
Clumsy Ninja Guide
Coins are what you will be using the vast majority of the time, to purchase items and equipment for your ninja. Because they are so necessary, there are a few different ways to get them. Every time you complete a training exercise or quest, you should receive a portion of Coins.
You are also able to unlock Animals, once you reach Level 10, and these bring in a certain number of Coins periodically, allowing you to earn money when you are not even in the game. Be sure to login every day too - there are Daily Bonuses that you can get for putting your ninja to sleep at the end of every day - you have to do this, just logging in is not enough.
Finally, you can also purchase Coins with real money, should you have a hole in your pocket.