Last March, we ended up with a group of 10, mostly family on our cruise on the Grand Princess. My hubby and I bought a bunch of tropical decorations at the party store and snuck around and hung them up on everyone's doors in our group. It was fun to hear their reactions! The crew got a kick out of us doing it. Instead of regular tape, we used a clear padded, double sided tape, precut into 1/2" squares. It was very easy to remove.
We also found some tropical party lights and hung them up on the balcony railing. It was so cool, hanging out there at night and having a drink. We even had a party out there.
Nothing better than sitting out there with a drink, listening to music and staring off into the night!
Enjoy your cruise!