Odysseus and his men have left the war and are sailing back home. As said in book 1, "...in his deep heart at sea, while he fought only to save his life, to bring his shipmates home."
Odysseus and his men are about to stab the Cyclops in the eye to blind him to try and escape. Him and his men have to wait till the Cyclops goes to sleep in order to try and hurt him. They know better not to kill him because they need someone to move that big bolder out of the way.
Calypso has been ordered from Zeus that she can no longer have Odysseus stay any longer. She must let him go on home. As said in book 5, "Hermes explains that he has bought with an order from Zeus that Calypso must not detain Odysseus any longer but send him on his way home." So Calypso is sitting down with Odysseus to let him know he has to go home.
Odysseus is ordered to go visit the land of the dead comes across one of his old shipmates. He explains how he had died and asks Odysseus for a proper burial. After he leaves the land of the dead he goes and gives his old shipmate a proper burial.
Odysseus and his men come across the two sirens. Odysseus had let his men tie him up so he can hear what the sirens are singing. And before letting his men tie him, he made sure they had beeswax in their ears so they won't hear the siren.