What had the animals done to prepare for Farmer Jones' return? What was the strategy for the animal's battle plan?

Snowball, who has studied books about the battle campaigns of the renowned Roman general Julius Caesar, prepares a defense and leads the animals in an ambush on the men. Boxer fights courageously, as does Snowball, and the humans suffer a quick defeat. The animals’ losses amount only to a single sheep, whom they give a hero’s burial.