-After making enough produce to make certain items, you can sell that animal and buy others to save money and time.
-If your animals are about to die from lack of water, immediately click on the warehouse and sell them. By doing this, way you will have some money to buy water and animals.
-When you see plenty of animals at the beginning, immediately sell half of them to get the money to upgrade. You can sell them as soon as the warehouse appears. Sell them before that screen appears to save even more time.