According to advice from feng shui practitioners as well as the Indian Ayurvedic tradition, it's best to position the headboard of one's bed to the south or east in order to promote the best possible sleep at night. Feng shui admonitions regarding positioning of a bed reach beyond just compass directions.
Feng shui guidelines call for the bedroom room door to be visible from the bed, without the foot of the bed actually facing the entry or any other door, including closet or balcony doors. In addition, the bed should have a solid wall or headboard behind it, rather than a window. In addition, the guidelines suggest that a bed should be placed symmetrically in the room, with nightstands on either side, rather than having one side of the bed against a wall.