Making it Functional
Before you begin to buy or borrow anything to put into your office, consider the empty space. If the walls need painting, now's the time to do it before a paint job entails moving bookcases or filing cabinets. If your home-based business involves customer or client visits, then you'll need a color that “fits” your business image (perhaps a heritage color for an antique store, for example), but if it's just you in your office, choose whatever will make you happy. Yellow is considered a productive color; blue is soothing; red and orange are energizing; and green is grounding.
What's on the floor right now? Carpeting can make the room warmer, if that's an issue, while laminate flooring is very easy to install and tends to be hard-wearing too. If the hardwood needs refinishing, now's a good time to do it, before you start hauling in furniture. If you're installing new carpet, refinishing hardwood, or painting give the room a few days to air out before you start working in it — even fumes from latex paints can be unhealthy to breathe.
Can following feng shui principles help my business succeed?
Commonly defined as the Chinese art of placement, feng shui certainly won't hurt. Principles include not sitting with your back to the office entrance, locating your office in your house's “wealth” corner, and using moveable items such as mirrors or candles to redirect energy flow from negative to positive.
You also need to consider wiring and lighting. Does the room have adequate lighting and electrical outlets? Can you place your computer and office equipment on the electrical circuit without overloading it and causing a fuse to blow or a circuit breaker to trip? You'll likely be in the office during daylight and evening hours, so assess the lighting from both respects. Can you meet your needs with floor or desk lamps or do you need an electrician's help to rewire the overhead lights?

