On his journey to Thebes Oedipus unknowingly comes across is father Laius at the crossroads; they fight and Oedipus kills him.
Laius and Jocasta leave their infant son Oedipus on mount Kathairon to die due to the prophecy that their family is to fulfill. The Shepard found him.
Oedipus paid the Oracle or Delphi to find out who his real parents are. When she told him of the prophecy he ran from it.
Oedipus wins the throne of Thebes by defeating the sphinx, therefore winning Jocosta's hand in marriage.
Tiresias, the seer tells oedipus that he is the killer of his father
After realizing the prophecy is true, that Oedipus did, in fact, kill his father Laius and married his mother Jocasta, Jocasta hangs herself; Oedipus stabs his eyes out, exiles himself and leaves Creon in charge of Thebes