What does Circe tell Odysseus he must do before he can leave for home?

Circe tells Odysseus that before he can leave for home, he must journey to the underworld to seek the prophet Tiresias. There, Tiresias will provide him with crucial guidance about how to return to Ithaca and deal with the challenges he will face upon his arrival. Additionally, Circe advises Odysseus to make sacrifices to the gods to ensure a safe passage home.