Planning on attending one of the many upcoming conferences - PHP related or not? You might check out some of the suggestions Lorna Mitchell has about being a good "conference citizen" while you're there.
I get to a lot of events and the crowds at each one are different and there's a different atmosphere - but at every event there are people who are making the whole thing less enjoyable for everyone else. Probably a lot of those people don't much care what effect their behaviour has on other people, but if you want to avoid being one of those people, these are my tips.
Most of them are pretty obvious when you think about them, but that's usually the problem - people don't remember the simple things like being quiet during presentations and taking every opportunity you can to use the times and spaces available outside of the normal talk schedule.