Click the big chicken in the coop to get eggs. The number beside the upgrades (the items on the shelf to the right of the screen) show how much each upgrade costs. The egg carton and chef are also upgrades. Just know that a couple of the power up are made to take eggs away. Pick your power ups wisely.
If at first when you click the green flag, if you immediately go into negative numbers just know it's a glitch and simply press the green flag again. It should be fixed after that.
