If there is an outlet near the door to the bedroom it may be possible to run extension cords into the room. In such a case, do not allow the extension cord to get overloaded. Extension cords are a short-term solution for guest rooms, bedrooms used infrequently or storage; but they do not constitute a long-term solution. Extension cords can be a choking or electrocution hazard, so don't use them in rooms with small children, and dispose of damaged cords immediately.
Consider running wiring from one outlet box to another over the top of the wall and concealing it beneath plastic or metal wire covers. Wall-mounted wiring sells as a kit or as separate pieces and may include mounting brackets in addition to covers. The outlets include mounting boxes, which extends from the wall to accommodate the wiring beneath. This solution is moderately simple because you must dismantle only one outlet box and extend the wiring from that outlet.
The best solution for a room with no outlets is to have regular outlets installed. Wiring is run from a central breaker box to different hub locations in the home. Hook up an unused breaker to the existing electrical system, or continue wiring from an outlet in a nearby room. Run the wiring behind the drywall or other wall surface, and install outlet boxes at intervals along the wall.
Building codes in some areas may require homeowners to consult a professional electrician before installing new wiring. If you are renting a home and there are no outlets where you need them, contact your landlord and request additional outlets be added. Your landlord may be liable for ensuring that each bedroom contain at least one electrical outlet in order to be considered a usable bedroom, according to city or town building codes.