1. Place the shadow clock in an open area where it will receive sunlight throughout the day.

2. Mark the position of the shadow cast by the clock's gnomon (the vertical pointer) at regular intervals, such as every hour or half-hour.

3. Label each mark with the corresponding time.

4. As the sun moves throughout the day, the shadow cast by the gnomon will move, indicating the approximate time based on the marks you made.

Remember that shadow clocks are not as precise as modern clocks and can be affected by factors such as cloud cover, the angle of the sun, and the location of the clock. They were commonly used in ancient times and can still be a fun and educational way to tell time.