Always have something at hand that can be used as a makeshift weapon. Not like, a knife or a gun - perhaps, a short pole of metal or a compass, just incase you're going to get ganked
If you don't want to hit the little kids, are you a good shouter? If so, shout death threats and scary crap into their faces. They might start crying, but, mission accomplished, right? Then of course, if the older guys pick a fight, you've already got what was mentioned in my step one
Call me a psychopath... but call me when this stuff doesn't work. :]
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Personally, if you get one of those chavs down, I recommend you to give him a curb stomp and the rest won't touch your fiery ass
