Club caps: You can wash off any dirt with soap and water, and a solvent like rubbing alcohol will help with grease/oils.
If your club caps are yellowing, it is likely because the TPU material is discoloring with UV radiation and oxygen. This is accelerated by heat, so we don't recommend putting them in the dishwasher. If you would like your caps to look fresh, you might want to get 2 sets of caps - one for indoor use when you want your clubs to look nice, and a set for outdoor use. You can find club caps and other clubs part here: https://flowtoys.com/parts-1/club-parts
Club body and handle: If your club body and handle are dirty, you can wipe them down with soapy water or rubbing alcohol. Do not submerge your vision clubs in water.