If you feel that someone is following you, you shouldn't be afraid to turn and look directly at them, eye contact is key and say "I'm calling the police if you don't stop following me!" or something synonymous. This may seem pretty bold to numerous people, but this is just what a potential attacker fears most; someone bold who might provide him problems. Carrying your keys and pepper spray inside your hand, while walking to all your destination is an excellent idea. I've seen quite several te...