as TS mentioned 'BULLIES AT PUBLIC PLACES'.
for a start, wearing shoes with good cushioning may be a good start if escaping is an option. wearing flip-flops might increase ur chances of flipping (or flopping e escape) over uneven ground.
. if outnumbered try out-talking the hooligans to buy time, while slowly backing off...
. carrying a glass bottle of designer water (got glass wan rite?), may deter some from upping e ante.
. den for e well-heeled, a tougher than nails time-piece is good for blocking hostile ~.
. ladies ought to get a bag that could be used as an improvised demolition ball.
. for those short-sighted a spare set always by ur side is a good idea.
& those who got loads of time should watch move kung-fu movies!