As the Cyclops has a peaceful slumber, Odysseus thinks of killing the beast who just devoured 2 of his men. His intelligence overrides his bravery. He stops only for the fact that he knew only the giant could move the enormous boulder that locked them into the cave. It'd be useless for Odysseus to leave him and his men to rot in this cave. They were forced to ponder till morning.
The Cyclops had milked his ewes and set out to face his chores for the day. He caught more of Odysseus's men for breakfast, leaving them scarce of manpower. He opened the giant slab just to let his sheep graze. Odysseus pondered on and on, wondering the worst ways to hurt the Cyclops.
Like Odysseus' prayers had been answered, a very large olive tree fell just before him. This sparked Odysseus' plan of revenge. He chopped a 6 ft section and placed it before his men. Together they crafted a stake with a sharpened end; hiding it well under the cavern before the beast returned.