EF-S rubber focus rings are now sticky, what's the best why to clean them?

The focus rings on my EF-S 18-55mm, EF-S 18-200mm and EF-S 10-22mm have got sticky leaving black marks on my bag. What would be the best way to clean the rubber off leaving just the plastic? I know I can google this but I figured I'd post here to find out from others what actually works.