You could try spraying catnip on the scratching post that you want her to use. If she isnt showing an interest in the scratching post, try one with sisal rope. My cat LOVES sisal rope. I have a scratching post with carpet that goes floor to ceiling in the living room. And another playground kind of scratching post in the back of the house which has legs in sisal rope. I also have a single short sisal rope one in the bathroom because she likes to lounge in there. And a think horse lead rope which is wound around to be twice as thick. I hung it from the ceiling near her tall post. She loves to swing and climb it.

I figure the more she has to play with, the less likely she'll play with the wrong stuff. :-)