Use a food-safe butcher block oil or mineral oil, rather than food oils like olive oil that will go rancid.Use the rule of hand when deciding how you should wash and care for the bowl; i.e. do not put the bowl where you would not put your hand.  No dishwashers, ovens, freezers, or microwave.The bowl should be cleaned with soapy water after every use, and oiled every 5-7 washings.If for display, make sure to dust it every month, and oil every six months