Although there are apparent benefits of moisturizing a tortoise's skin or shell, it usually isn't necessary. The skin and shell of tortoises, and indeed reptiles in general do not absorb water. Moreover, many moisturising products might not be safe for reptiles.

Can I put oil on my turtles shell?

Make sure water is not too hot. Then pick up and hold turtle carefully because they will be oily, slippery and wiggling. Rub the oil into its skin and shell. Your hands will be oily of course afterwards just wash them with soap and hot water.

Can I put olive oil on my tortoise's shell?

The only thing you would need to put on your tortoise's shell is water! Do not use any oils or other substances! It was common practice to oil the shell of tortoises years ago.