How to dress for this character?

Hi there! So im in highschool and for french we have to dress up as a character and talk about our life as that character. My teacher gave me the role of St. Augustine. The problem is that he lived almsot 2000 years ago and i have no idea how to dress up as him. Please give me some ideas!!! i was thinking of wearing sheets as a robe and making a bishop hat. but more ideas will be helpful