Copenhagen - One day trip- Things you can see!!!

I am going on a trip next week. I will spend only one day in Copenhagen. So I really need advice. Copenhagen - One day trip- Things you can see!!! I dont know what is the best way to get to know city for just a short time. Any advices and opinions are welcomed. Thank you in advance.

Copenhagen is a beautiful city. I am certain that you will love it. I spent there couple days. So I tried couple organized excursions trough the city. The first was with a bus. We visited about 20 interesting places in one day. There are a great palaces there. I liked Amalienborg Palace and Rosenborg Palace. I am sure that you will like them also. You must also see Tivoli gardens. It was breath taking. I loved it. I have spent there couple hours ( but you dont have enough time). The second excursion was with the boat. And that was also very nice experience. Copenhagen looks different from the water and different from the ground.