When you have a power socket, light switch or TV aerial outlet etc, that needs to be wallpapered around I use a small set of scissors around 4″ – 5″ (100 -125mm) long to make the appropriate cuts in the paper.
Hang the strip of wallpaper as you would normally from the top (see post on pasting and hanging wallpaper), when you reach the power socket etc, make four cuts in the paper from approximately the centre of the power socket etc, to each of its outer corners (see fig 1), cut these four flaps of wallpaper down to leave an overlap of the power socket etc, of around 3/16″ (8mm). See fig 2.
Turn off the main switch at the consumer unit and remove the appropriate circuit fuse or miniature circuit breaker (MCB), check that the power socket etc, is ‘dead’ (no voltage present).
Loosen the fixing screws holding the power socket in place and, using the wallpaper brush, guide the remainder of your flaps of wallpaper behind the power socket. Look out for any blobs of wallpaper paste that may have dripped onto the electrical connections on the back of the power socket. If there are any present remove them with a dry paint brush and /or a cloth.
Wait until the wallpaper paste has dried out, then replace the circuit fuse or Mcb and switch the consumer unit back on. Check the power socket is working correctly.
One final piece of advice is that if your switch or socket is looking a little tired or even grubby, why not purchase a new one to make it look the part, you don’t want beautiful wallpaper ruined by an ugly, grubby or even broken switch. There are thousands on the market so a good place to start looking online is here at B & Q.