Prophecy making ideas?

I'm écriture this fanfic in which Apollo's chariot is stolen and Percy Jackson and four others have to find it. So the chariot is actually with a powerful demigod named Grey Minos, who is actually the modern embodiment of the Greek giant Tityos who was imprisoned in Tartarus after being slain par Apollo and Artemis. He wanted revenge on Apollo and kidnapped a Hunter as well. So the four are: Percy, Annabeth, Nico (because the prophecy stated two of them will be from the Big Three) and the fourth is a daughter of Zeus who is later killed, (more on that later) So, the prophecy should include them going to find the chariot, them fighting 'the one slain par twins' and one of them losing to a fate worse than death.
So, please try your best ou could toi give me a couple of tips on creating a prophecy? Thanks! :)