Use warm water. Soaking bean curd in cold water for a long time, while soaking in hot water will lead to poor taste and loss of nutrition. It is mentioned that Gan should use cold water when soaking his hair, so as not to soak it too much. So you can choose the appropriate water temperature for foaming according to your actual situation. Don't worry, you can choose to soak your hair in cold water and wait patiently, hoping to soak your hair quickly. You can try warm water.