1. cleaning: clean the insulated lunch box before using it for the first time. Wash the inside and outside with mild detergent and warm water, and rinse thoroughly.

2. Preheating or precooling: In order to keep the temperature of food better, it is recommended to preheat or precool the insulated lunch box before use. For the food to be kept warm, pour hot water into the lunch box, let it stand for a few minutes, and then pour out the water. To refrigerate food, you can put the insulated lunch box in the refrigerator for precooling.

3. Ensure sealing: Before loading food, ensure that the insulated lunch box is well sealed. Check whether the sealing ring or sealing cover is in good condition, and ensure that the lunch box can effectively keep the temperature of food.