My advice is to fight back but to a certain degree for example if he is waiting for you at the bus stop walk straight up to and don't look unconfirdent and spray him in the eye with peper spray ( if this is not avliavble then use some bathroom spray or aerisal ) after doing this make sure he is on the ground maybe you will need to trip him up after just start shouting at him when hes on the ground e.g. insults if h trys to get up spray him again and maybe a bit of psyiccal force (odn't worry about making him blind it will not happen the eye will produce water to protect from going blind this may not seem like the nicest way to aproch this situation but then again any way you do will not be nice