A lot of my walls are painted white so this is a simple way to protect paintwork from grubby finger prints and at the same time add some colour and interest to my walls
For safety reasons turn off the power to the circuit before removing your light switch and make sure it's done by a competent person to avoid a short circuit.
Purchase a pack of clear plastic light switch finger plates. I bought a pack of two on the internet for £2.25 (free postage) as my local diy stores only had white ones.
Cut a template using wallpaper scraps, wrapping paper, greeting cards or design your own to match your room.
Carefully unscrew the light switch and place the paper and finger plate into position behind before screwing back into place (make sure the wires haven't loosened).