How would you get rid of a person lurking around your window?

I live in an apartment near a college town and i've been robbed once and recently I caught a person looking into my bedroom window twice. So I put up curtains and nothing for a while but I heard it again and its winter so I could see his footprints but i didnt see him. I know where he will walk but I don't know what to do to catch him i was thinking like a bear trap or something (not cheap or safe) and I don't think cameras will help its dark.