Dress in layers - it can be cool at night and in the morning, but hot during the day. A cami or sweatshirt you can tie around your waist or dump in a locker. Also, for me, I like a simple small purse with a long strap so I can carry my important cash, aspirin and sunglasses, but I'm not lugging around a mother load and trying to wedge my purse in on all the rides.
For me - capris, simple tank and a comfortable layering cardi or sweat shirt
We wore shorts and tshirts during the day and then went back to the hotel to freshen up and changed into capris/jeans and a casual shirt for dinner. Luckily just about anything goes there so you shouldn't have to worry too much.