We celebrated our daughter's 13th a couple of weeks ago on the Fantasy. We brought a banner with us and asked our stateroom host if he could hang it while we were out on an excursion, so that when we returned, it would be there to greet our daughter (along with a cake we had pre-ordered and arranged to have delivered to the room while we were on the excursion). He was fine with helping, and when we got back to the room, he had taped it up across the center of the room (where the curtain could be pulled across, which gave him more surfaces for taping). Thus, while you might not want to attempt any tape-jobs yourself (at risk of using something "illegal"), our stateroom host was very happy to help (and obviously knows what is acceptable to use....he just used what appeared to be normal, clear Scotch tape). Much to our surprise, he also made a pretty big birthday cake out of rolled up towels, including a towel candle and lots of little stickers all over it to make it appear decorated. That earned him some additional gratuity, for sure!