Simple! Easy! The rules are simple – if you had a skyscraper floor, what would you put in it? Why would it be special? Etc! 1st person does Floor 1, next Floor 2, and so on!
Post your posts like this:
Floor #
This floor is home to bla bla bla. Why? Because yadda yadda yadda yadda yadda. Also, it has yabber yabber yabber yabber yabber. It also has yeah yeah yeah in it. Nah nah nah.
Floor 1
This floor looks like an ordinary hotel lobby by day. At night the laws of physics become rather malleable.
This floor is an open field where people do jousting tournaments on whatever animals they wish. This includes fantasy creatures and animals who normally cannot support a human being.
This floor has no floor. It's just a big empty pit with walls and an elevator shaft. A seemingly endless stream of flooring contractors keep coming up the elevator and falling to the floor below.
This is where the tavern is located. Boasting grand views and a grand interior, people from all walks of life dine and drink here. Otherworlders have also been known to hang around here and the food and drinks here are known to have strange effects.