Feng Shui within a room

[myfs_102930]

Hey everyone, im a teenager who has no say on how the rest of my house is arranged, but i would still like to make use of feng shui within my bedroom, so if you could perhaps provide some advice, some links to information, or anything you think would be helpful, i would appreciate it! More specifically, should i treat my room as just a single entity, or should i divide it into sectors? Also, should i make use of true compass directions, or is the wall with my bedroom door automatically considered 'north'? Any advice is welcome!