Hi jellyfish, not something done often except for hanging lining paper but can be done easily enough. Start by measuring around an inch down from the ceiling at both ends of the wall you intend starting from and snap a chalk line between the 2 points. Make sure this is level using spirit level. It is best to get it straight as otherwise it will look terrible by the time you get to end and using the edge of the wall or ceiling will not be good enough. Hang the first sheet of paper to this line and trim off the top. When you paste the paper concertina it and this wil make it easier for you to hold and hang. As with all wallpaper it is best if you can to hang it from the lightest part of the room, ie close to the window or light source as this will hide the joints better but it's not esential with this way of hanging it. Hanging the paper horizontally will make the joints show more than by hanging it vertically so try to get them as close as possible without overlapping. I would have a couple of pairs of steps and a plank available too as this will make putting up the first and maybe second pieces easier for you. Good luck. Shed.