I agree with puddingburner , been there done that and yes its all about reading people and prevention , stopping it before it kicks off , of course you need to be able to handle yourself when the time comes , but remember door staff work better as a team you go it alone and you will have claret on your hands.
I have changed my proffesion now and have become a bum doctor as i was so experienced at spotting all the different types of arseholes that go out fri, sat , sun.
On a serious note mate good luck, but remember its team work and supporting your colleagues that gets the best results. Bully