You'll eventually reach stages where you are required to match three eggs in order to hatch a set number of chicks. However, it's all too easy to let the required eggs overrun the board. You should pay close attention to their positioning, and you should try to make moves that keep the eggs mostly in one section of the field. That makes it easier to make critical matches and it leaves you with more of the room you need to match other sets with multipliers to improve your score.