While it is true that cats scratch upright objects like furniture to sharpen their claws, this is not the main reason for doing so. The main purpose is as a form of communication to other cats. To other cats it provides a visual indicator that another cat is in the area. It may also give other cats an indication of the other's size. The scent glands found in the cat's paws also leave additional information. This is a natural feline behavior, unlikely to be extinguished, nor would it be wise to attempt to do so, as any effort to undermine an animal's natural inclinations inevitably results in a disastrous behavioral and/or physical response. However, with a little patience and ingenuity and, hopefully, a minimum of inconvenience, you can redirect you cat's attention from your furniture to a more appropriate scratching outlet.
You will find a variety of scratching post surface types available from which to choose. It may take a bit of trial and error to find which appeals best to your cat. Perhaps the best place to start is with something that has already proven to appeal - i.e. the surface material of the targeted furniture. Many cats seem to enjoy posts wound with Sisal, a natural fiber made rope like. Whatever the surface, the post itself must be stable. If it is unsteady, your cat will likely avoid it.
As they say, old habits die hard and regardless of the luxuriousness that your new scratching post may offer, you will very likely have to find a way to make the unwelcome scratching focus inaccessible or less appealing. For instance, most cats will not be comfortable scratching a surface covered in two-way (carpet) tape or aluminum foil. You should also remove the scent markings with a pet odor specific cleanser and then spray with a citrus based cleanser, as cats are not particularly fond of citrus. Position the scratching target in the immediate proximity of the scene of the crime.
One way to increase the attractiveness of the new scratching post is by providing your cat with some toys made of the same material as the post. You can also play with your cat and these toys and try attaching them in an enticing manner at the top of the post. Rubbing a little catnip onto the post or even making a pot of catnip tea to spray onto it can further increase your cat's interest. (Do the spraying in an area other than the problem area, so as not to get any on the wrong surfaces.)
If the position of the scratching post is not ideal, from your idea of a Home and Garden pictorial perspective, you may slowly be able to move it to another area, but be prepared to have to stay in the vicinity. One reason your cat may have chosen to scratch that particular piece of furniture may have been due to its location. Scratching is supposed to be a communication signpost, so close proximity to the habitants of the home would seem ideal to a cat. You may have noticed that your cat likes to scratch after a nap, so another post in the area she likes to sleep is also a good idea.
Animal Behaviourist John Wade (http://www.johnwade.ca/)