Need advice for concert

[Rocky]

Okay, so I found out just the other day that I will be going to a club the night before Halloween this year, sweet. However, this is unlike any other concert I will be going to, because there will be DJ Tiesto there playing a 4+ hour live set of music. I would put Tiesto under a trance/house type of music that he plays, which I listen to a lot but I've yet to go to an actual performance. He will be playing in a club of sorts, and I will have a general admission ticket, so I'll be milling about with everyone else there.

Besides that, I am completely clueless as to how should I prepare for such an event. Since the place is going to be in a club, should I dress up? Or should I wear a crazy outfit, since it's going to be playing through Halloween morning? Should I bring water? camera? extra money? Should I stay away from the scary looking dudes that offer me drugs? what else should I look for? Anyone with experience for going to club performances or raves or what have you, some advice should be greatly appreciated. Hopefully Bryan will give me a response as well, since he DJs and knows whats up.