You don't have to see danger to avoid it. Trust your instincts. If something feels wrong to you, the go to safety and contact the Police. Don't be too trusting. It is easy to get complacent on a college campus.
Most people are friendly, but be careful.
A little paranoia can be a good thing. Listen, if you hear someone approaching you from the rear, look around. Maintain a safe distance from suspicious people to give yourself time to react, or to avoid attack. Avoid using alcohol or illicit drugs. Their use can impair your judgement, slow reaction times, as well as expose you to some less than desirable social situations and people.