The best way is not to use it, its a flawed design (its only purpose is with racing gloves). Without gloves it will deteriorate faster because of the oils from your hands but it would still wear smooth with gloves. I know with suede there are brushes to bring the surface back but that over time is just rubbing the material away, if you really want to keep it nice, you need to re trim it when it wears away or take it off (and get a leather wheel) until you sell the car