1. Turn on the instrument and wait for the instrument to warm up to the standard temperature.

2. Take out the calibration certificate or calibration label, check the validity period of calibration and confirm the calibration time.

3. Prepare a clean standard cloth and put the cloth on a clean workbench to avoid contact with the instrument.

4. Turn off the power supply of the instrument, put the instrument on the standard cloth, and ensure that the instrument head is in complete contact with the standard cloth.

5. Press the "Calibrate" button to start the calibration procedure. During the calibration process, the instrument will give a sound prompt and a screen display, and after the calibration is completed, the instrument will automatically exit the calibration mode.

6. After the calibration is completed, take out the instrument, clean the standard cloth and reinstall it on the instrument for the next calibration.