It's a fact: many of the people I've seen in concerts don't know what to do once they get there. This can sometimes lead to conflicts, and trust me, there's people at concerts you don't wanna mess with. Here's a few pointers at how to behave at a concert...
First of all, you have to be dressed for the occasion. It's good to see metalheads at classic rock concerts, but you're not going to expect a hippie at a Slayer concert right? The same goes to those pink bubble pop princesses, you're going to be eaten alive. If you're going to be dressed like that, go to an Avril Lavigne concert. The style that works for EVERY concert is a black T-shirt and jeans. You can never fail with that.
Another thing is to treat the concert with the respect it deserves. If it sucks, then boo, man, don't be ashamed, but don't boo in a show where you see that everybody's having a good time; you'll ruin the mood. And that sucks.
Also, respect your fellow concertgoers. For example, if you're going to be filming, at least give it a rest for a while so the others can see. In fact, just take pictures, it's simpler, besides, the audio in most cell phones sucks. If you request a song, make sure you're damn near or you're just going to annoy the hell out of everyone. If you mosh, do not clench your fists, because you WILL hit somebody, and he'll make damn sure you pay. If you take someone down, please, help him up, lest you want to let him die trampled under the crowd. Also, if you're going to sing, don't sing off key, at least sing in your voice. Everybody will appreciate it.
If you're going to buy beer don't throw it away, two reasons: It's damn expensive at a concert and you're going to drench everyone in front. Also, don't bring babies or toddlers, it just looks bad. Girls, if you're going to flash, do it quickly, well, if you don't want to be taken away by security. Don't bring drugs, because you WILL be caught. Trust me, people will notice.
One last thing, just have fun! Going to concerts is about the good times, the people, and the music. Don't see a band you don't like, see the ones you do, those are the ones you'll enjoy! Seeing your favorite bands is one of the ways you can feel true happiness, at least for a while.