I'm decorating my room and i am 13 years old and im totally stuck for what colours to decorate it but my mum said i cant have a white duvet because i might get make up on it please help?

The logical thing to do then is stop wearing makeup.
_________________________________________________________________

Or you could look for a multi-colored bedspread or duvet like this, that would hide stains better.

http://www.neimanmarcus.com/store/catalog/prod.jhtml?itemId=prod43750191&ecid=NMCINexTagFeed&srccode=cii_9324560&cpncode=18-50056498-2

And then instead of a white duvet, you can go with a white ( or beige, or cream, etc.) wall.
For tips on walls, look here:
http://www.housepaintingtutorials.com/interior-paint-colors.html
Good luck!