To keep your luxury watch in pristine condition, avoid exposing it to extreme temperatures, magnetic fields, and harsh chemicals. Regularly clean the case and bracelet with a soft, dry cloth. For leather straps, avoid excessive moisture and direct sunlight. Ensure your watch is serviced by a certified professional every 3 to 5 years to maintain its functionality and prevent internal wear.

If your luxury watch stops working, first check if it’s an automatic or manual-winding watch. If automatic, try wearing it for a few hours to see if movement restarts it. If manual, try winding it fully. If the watch still doesn’t work, it may need servicing or repair. Bring it to a certified watchmaker or the brand’s service center for an accurate diagnosis and repair to avoid damage.

To authenticate a pre-owned luxury watch, look for the following:

• Serial and model numbers: Verify these numbers match the brand’s records.
  
• Paperwork and certificates: Check for original papers, warranty cards, and receipts.
  
• Authorized sellers: Purchase from reputable dealers who offer a guarantee of authenticity.
  
• Watchmaker evaluation: Have a certified watchmaker inspect the movement, materials, and construction.

If your luxury watch is running too fast or slow, it may need regulation. This is common with mechanical watches and can be resolved by adjusting the movement’s balance wheel. Take your watch to a certified watchmaker or the brand’s service center for an inspection and adjustment. Regular servicing can prevent timekeeping issues and maintain the watch’s precision.

Not all luxury watches are suitable for water activities. Check your watch's water resistance rating:

• 30m (3 ATM): Suitable for hand washing, but not for swimming or diving.
  
• 100m (10 ATM): Suitable for swimming and snorkeling.
  
• 200m+ (20 ATM): Suitable for professional diving.
  

Ensure the crown is fully screwed down and avoid using the chronograph buttons underwater. If unsure, consult the watch’s manual or the manufacturer to confirm its water resistance capabilities.