lol, please excuse confusion between American English and English spelling ie differences between the way things are spelt in Photoshop menus and my conscience ;).

• Make sure that the top layer in the stack is highlighted in the layers palette.
• Go up to the top menu and select layer> New Adustment Layer> Color Balance
• Select OK on the 'New Layer' pop up window.
• A new 'Color Balance' layer appears in the layers palette and a 'Color balance' window will appear.
• Play with the colour sliders, you will note that by sliding them towards the opposing colours, the colour of your image will change.
• Do this until you have a colour that you are happy with and click OK.
• You can always get back into the 'Color Balance' window again to change your colours at anytime by double-clicking on the 'Color Balance' adjustment layer in the layers palette.
• If you like, you can add more color adjustment layers to make different colour variances with different layer modes...
• If you are clued up on them, add a layer mask to the coloured layers as well and gently paint out areas of colour so that you can get more than one colour into your background ;)