You need to scan the QR code in the manual to download the application, or search and download "H Band" in the application market
Or visit: https://www.vphband.com/hband/hband.html
Turn on the Bluetooth of the mobile phone, select [Settings]-[Devices] in the APP, and select "S16" to connect
Once the connection is successful, the date, time and language on the watch will be automatically updated