Making 55-degree gray ice cubes requires a special ice cube mold, and the specific operation steps are as follows:

1. Prepare a glass of mineral water or cold boiled water and pour it into the ice compartment of the mold, being careful not to pour it too full.

2. Cover the mold, put it in the freezer, and wait for four hours before taking it out.

3. Knock on the back of the ice cube and take out the ice cubes to enjoy.

The following points should be paid attention to when making 55-degree gray ice cubes:

1. The color and transparency of water may affect the production result. You can try to make it several times to get a satisfactory gray effect.

2. When using the mold to make ice cubes, make sure that the mold is clean and sterile to avoid bacterial growth.

3. When using the refrigerator to freeze ice cubes, ensure the safety of ice cubes in the refrigerator, and do not put containers such as cans into the refrigerator to avoid explosion or deformation of the containers.

4. When taking out the ice, pay attention to safety to avoid injury.