If you've chosen an accent colour for a room and just have one accessory in that colour then it can look a bit odd. Add a couple of accessories in your chosen colour to balance the room. Team artwork with cushions, and you could also try some fresh flowers as a nice way of adding a splash of colour. Little flashes of colour can add to the overall effect too.
Take this fab lampshade. This really cool lampshade is made of aluminium with a red inside.
The cut out slash in the side allows you to pop the shade over a lightbulb and at the same time it reveals a flash of colour. Very subtle, very versatile. I really like this idea.