I'm going mad trying to decorate!

[Loveagoodbook]

I'm currently decorating my living room and I'm stressed!
I have a beige ish carpet and in the process of probably getting a light grey sofa.
Painted 3 walls an off white, but stuck what to do with the forth!
It has to be papered as it's in an awful condition.
I was thinking of a grey colour, but now I'm thinking of something with more colour, anyone got any nice colourful wallpaper that they can share?