Suggestions on Vegas Wedding

My husband and I are planning to get remarried on august 9th in Vegas. It will be just the two of us. We also are taking this trip to celebrate our 40th B-day. My question is: what should I wear? Long, short, white, blue, yellow... Where do you recommend as a good place in Vegas. I'm Portuguese/Brazilian and my husband American and we both have not been in Vegas before. So it's going to be our first trip (and together) to Vegas. Hope to get some tips form David. Thank you!