I'm going to Vegas, what should I wear?

OK, I went to Vegas for an "academic-related" convention right after I turned 21. The problem was, none of my friends were 21 so I sat around and gambled a lot but wasn't able to go out at night. Now that all my friends are 21, we're going over the 4th of July weekend. I generally consider dressing up as jeans and a polo, and dressing down as jeans and a tee shirt. I'm not saying I have no style, I have just become too comfortable in the college life where no one cares what you're wearing. I am not looking to hook up with a bunch of randoms or attractive high cl prostitutes either, but who doesn't like a little extra attention in sin city? Thanks for the input!! I prefer advice from the female gender haha. What would you want to see a guy wearing in Vegas?