Soap, water and a soft cloth. Carbon fiber in resin is chemically stable and needs no conditioning. The care that matters is protective: it chips at edges under sharp impact and the exposed fibers are delicate, so the risk is dropping the knife rather than anything you do while cleaning it.
A damp cloth handles almost everything. Carbon fiber is usually polished smooth, so there is no texture trapping grime the way there is on G10.
Avoid abrasives, which will dull the gloss and expose the weave unevenly.
Edges and corners. A hard drop onto concrete can chip a carbon fiber scale where G10 would simply mark. Once a chip exposes the fiber ends, moisture and handling can work at it.
This is the honest counterpoint to carbon fiber marketing: it is exceptionally stiff for its weight, and it is not tougher than G10.
Polished carbon fiber is slippery, particularly wet. If the knife will do wet work, that is worth considering against the weight saving you are paying for.
See the glossary entry for the full picture.