The instructions are in the game, but ill say them anyway. Use the up and down arrow keys to make the bird go up or down. Collect the coins, but avoid trees and other birds. If you it one, you will lose a life. Its game over when you run out of lives.
credit to @CosmicHamster I did a couple more scripts so the coins move and you move faster and also a high score which @CosmicHamster is adding in to the original