I need an interesting pattern to decorate my room with, can you help?

I have just painted my room white, and now the paint is dry i would like to add some kind of border or interesting pattern.

i have:

- a pot of brown paint
– a roll of masking tape
– a pencil
– a tape measure
– a spirit level

i would be very interested to hear any ideas you have on how i could decorate one or all of my walls with this. i would also be interested in any pictures you can link me to with simple patterns or designs that i could pencil on to my wall and then fill in.

thanks.