Karen Anne asked, "How does one hang wallpaper on the ceiling?"
My short answer is, "It's a pain in the neck."
Literally as well as figuratively.
The long answer is, it's much easier with two people. If I had a helper, I would've cut the strips of wallpaper the same length as the room(actually, a couple inches longer) and while my helper held up one end against the ceiling, I'd go along with a clean mop or a Swiffer sweeper or something like that and push the rest of the length of wallpaper all along the ceiling until it was nice and smooth and even. That way, the paper would be seamless the length of the room.
Alas, I had no helper. ....Sigh.... That makes the whole thing trickier. I had to be careful not to cut the strips of wallpaper any longer than I can reach, so that I could push the whole length of paper against the ceiling until the paste "grabbed". Otherwise, gravity works against me and I end up with a big ole mess. (That's the voice of experience speaking there.)
I wish I had long extendable arms like Inspector Gadget. "Go, go, gadget arms!" I'd yell, and then be able to put up a 13-foot-long strip all at one time. I decided to cut all the strips of wallpaper 24" to 30" long so that they looked kinda like panels, because it's impossible to hide all the seams. (And, if I'd used those plyboard beaded panels, I'd have seams anyhow.) So, hanging paper on the ceiling all alone involves a lot of climbing up the ladder and then standing there with your arms above your head, palms pressed against the ceiling, smooshing pieces of wallpaper around until they stick, at which time you climb down the ladder and look up at the ceiling to see how crappy it looks, and then climb up on the ladder again. Over and over and over.... See why I said it's a pain in the neck?
And when the whole laundry room ceiling was finally--after three days--covered with paper, I went back and stuck down all the edges and corners that had popped loose, and then I painted it. Two coats. With a pale greeny-blue that's so pale I had to look twice to make sure I hadn't missed any places. The color is Valspar's Luna, and I love it. Depending on the light and the weather, it goes from pale gray to soft blue to very light green.
It was a pain in the neck to do, but I really like my (fake) beadboard ceiling.