1, you can use the oil to fry the pig's feet slightly (if it is better to use a little lard), to facilitate the protein later melted into the soup; 2, with cold water under the pig's feet to cook; 3, the water at a time to put enough water, do not add water halfway through the soup; 4, cover the lid of the pot on a high fire to boil and then cook over a low fire; 5, with casserole do not use stainless steel pots; 6, with an open fire, do not use electric stoves or induction cookers or electric casserole. First thought of these - the old greedy cat