Sphynx lack fur and therefore get oily skin and also sweaty. They require frequent baths to maintain healthy skin. Your Sphynx kitten should already be used to baths if you received it from a quality breeder.
You will need:
Gentle shampoo or soap (Johnson & Johnson baby shampoo or Aveeno works great)
Shallow sink or tub with warm water
Start by taking two tbsp of coconut oil and rubbing it on your Sphynx’s skin to loosen the dirt and wax build-up. If your cat is allergic, olive oil works great too. Let sit for 5 min, then put cat gently in sink of warm water about chest deep on cat. Lather cat with shampoo making sure to clean between toes and get tail. Use wash cloth to clean face, ears and extra grimy spots. Rinse cat gently and wrap like a baby and dry.
You can use a small amount of oil like lotion to moisture skin if needed.