The weather cannot get any better than it is in Aruba. It is in the 70s and 80s in the day and then drops to the 60s and 70s during the evening. So you can wear your cute beach clothes during the day and have no probably wear pants and a light sweater at night.
Some of the things you must do:
1. Eat at Flying Fishbone--This is the most romantic place to eat in Aruba. You can get a table for two actually on the beach, so hang up your purse and shoes and let the sand and sea get in between your toes while you celebrate your new life together. Make sure to make reservations.
2. Kukoo Kunuku--If you are looking for a fun night out as new husband and wife this is the perfect thing for you to do. A old festive school bus will pick you up at your hotel and then you will travel around the island picking up other fun loving travelers from their hotels (most were newlyweds on the one I went on). The night is all about what people in Aruba actually do for fun. You will have a champagne toast at the light house, eat a traditional Aruba dinner, and stop at numerous bars. It is such a blast!!
3. Visit the Natural Pool--This is something I wanted to do so bad, but we ran out of time. The Natural Pool was rated the #2 Thing to Do in Aruba according to tripadvisor.com. You must rent a jeep and find this spot just the two of you.