Book Reports / Oedipus Essay- English Class (symbols of blindness and sight examples) [2]

My task is to write an essay on Oedipus the King. My question to be answered is.. give some examples of how the symbols of blindness and sight are connected with the themes of ignorance and knowledge in this play. How do you think the solution to the riddle illustrates Oedipus knowledge and ignorance?

Right now I really would like to start off with an outline and i am having a hard time with a thesis statement. If anyone could help me that would be great thanks!