How do you set the day on a sharp spc900 atomic clock?

To set the day on a Sharp SPC900 atomic clock, you typically need to press the "Mode" button until the day setting starts flashing. Then, you can use the "+" and "-" buttons to adjust the day to the correct setting. Once you have selected the correct day, you can press the "Mode" button again to save the changes and exit the setting mode. Make sure to consult the clock's manual for specific instructions tailored to your model.