How do you remove an oil stain from a cotton shirt?

To get the oil out , put baby powder on it, let it soak up the oil, shake off excess, ( this works best when stain is fresh, and wont work on silk) then launder in machine but pre- treat with a stain remover first. Machine wash it at the highest temperature allowed. for the shirt. Put bleach on it if its a white shirt that can take bleach. before machine washing.