Materials: mold, mineral water (or cold boiled water)

1. Take a mold specially made for making ice cubes, wash it and dry it for later use.

2. Prepare a cup of mineral water or cold boiled water.

3. Pour water into the ice tray of the mold, be careful not to fill it too full, cover the mold and place it in the freezer layer of the refrigerator.

4. After four hours, take it out and knock the back of the ice tray to remove the ice cubes.

5. If the ice tray is frozen and hard to take out, rinse the front of the ice tray with cold water and repeat step 4.