Wallpaper and Wallcoverings - angled walls

I am papering some rooms in an old house and the the upper floor has angled walls, or angled ceilings as some would refer. One small room I am doing has this type. And they want it papered. Since I have never papered the angled part before , how hard is it to keep the paper straight as I paper down the wall, with the wall not being plumb. Before I attempt this job I would like to hear from those who have done this. There are a slim few jobs that I have had to make the paper look level otherwise, being plumb looked unlevel because of structural shift. Just need some feedback. Hope I am making myself clear on the description of the project. Thank You, Aydia

hang the paper straight by using a plumb bob or spirit level
from the ceiling line to your base boards.
Hanging your paper "crooked" to compensate for your "angled walls & ceilings is not the answer because If your floor is level then any furniture and such like against the wall will show the patern sloping up or down hill!!
The best answer is to use a paper that has little or no pattern. Avoid using papers with vertical stripes.
There are papers available that have random designs that can look OK in a house like yours.

Just thanks for the advice on wallpapering angled walls. Sincerely, Aydia_here