You must turn the dollhouse upside down to apply ceiling paper to the second floor rooms.
Make paper templates of the ceilings and then cut them out on your ceiling paper. It is the easiest way to have a continuous ceiling, with no patches or joints.
Ceiling trim will hide the cuts. It is also best to apply your trim now while the dollhouse is upside down.
Keep In Mind
Keep your dollhouse from tipping over by using binder clips to clamp support pieces to the back of the dollhouse. You can use any dollhouse part that is long enough to do this. They make great temporary "legs".
