Hotels have things going on but anyone can go to them, most of the crap is on the beach front.
Just wear going out clothes for nights and beach stuff during the day I guess. American males dont like actually getting dressed up to go out, they think you are gay if you actually try look good...or metrosexual as they say. But the girls all like guys who get dressed up. Just wear what you would on a night back home.
Im heading down 18th march to 25th.