We taught my daughter go poo poo by taking her to the potty in the morning after the milk, and saying "ng......ng......ng..ng..ng.." Then later, she can have poo poo regularly, not on the diaper. Then one day, she can tell us she wants to poo poo by saying "ng.. ng.."
My friend told me not to teach her wee wee so early because once she doesn't want to wee wee on the diaper, we will be difficult to find toilet for her when we take her outing. And it is disgusting to clean the public toilet seat for her.