Age: 1. Charge the device using the USB cable for 1 hour. 2. Choose the appropriate grinding head based on skin condition: fine sand for daily care, rough sand for removing dead skin. 3. Apply the chosen head to the foot, using low speed (1700x/min) for gentle exfoliation and high speed (2000x/min) for tougher skin. 4. Do not apply too much pressure to avoid injury. 5. Clean the heads after use. 6. Store all accessories in the provided bag to prevent loss.