The answer is found in Book 12 in the Odyssey towards the beginning
Answers 1Add Yours
Tiresias told Odysseus;
1) that they would encounter the grazing herds of Helios on Thrinakia, but that no matter what happened they should avoid them.
2) He gave the prophecy that if Odysseus or his men ate the livestock they would meet with destruction.
3) He told Odysseus that when he would encounter ignorant men, courting his wife and eating his food when he returned home.
4) His wife's suitors must either be killed or sent away.
5) Odysseus was told to find the place where no man knew of the sea and ate only unsalted meat. In this place someone would see the oar he'd be carrying on his shoulder, and would ask, "What winnowing fan is that upon your shoulder?" Odysseus should then stick his oar into the ground and make a sacrifice to the Poseidon.
The last thing Tiresias told him was that after accomplishing all these things he could return home.