Working platform for hanging the wallpaper
You will need to build a suitable, safe platform to enable you to reach all areas to be papered. This will vary according to the layout of the staircase.
The other big difference between papering a room and papering a staircase is that some of the lengths of paper may be quite weighty and long. An assistant will make the longer drops easier.
Start with the longest drop first. Plumb a vertical line for this allowing for an overlap into the corner of the head wall.
Measure carefully, being sure to allow for the angle at the bottom of each drop.
Cutting pasting and folding the paper
Cut and paste in the normal way, although some people find it easier to work with concertina folded paper. as for a ceiling, on the longest pieces.
Hanging and trimming the wallpaper
Unfold the top, line up with the vertical mark and work your way down the wall in the normal manner. Trim each length as you go. The only real difference is that you will have to do a little more in the way of climbing!
Continue hanging paper either side of this longest drop until the wall is complete.
Work round the walls of the staircase as you would for a room.
If your working platform relies on the support of a ladder on a wall, this wall will need to be left until last. If that is not practical in terms of pattern matching, then, once it has been papered, leave to dry overnight before covering the end of the ladder with plenty of soft material and using the wall for support again. When papering this wall from a ladder or platform resting on it, you will need to move it to one side or the other to gain access. Each time you move the arrangement, double check that it is secure and stable before climbing on it.
Never stand a ladder sideways on a staircase. The base of the ladder must always be sited at the tread / riser internal angle to prevent it slipping.
Where a handrail meets the wall, it will be necessary to trim the paper. To do this, hang the paper down to the handrail and mark the centre of the rail approximately. Make a horizontal cut in from the nearest edge of the paper to this mark. Now make a series of radial cuts out from the mark, a little longer than the radius of the handrail. Carefully manoeuvre the paper around the end of the handrail and mark and trim the small flaps.