You can use Wi-Fi as an alternative to the mobile network when establishing an internet connection. This way your smartwatch doesn't use mobile data.
Press the Home key.
Press the settings icon.
Press Connections.
Press Wi-Fi.
Press Wi-Fi.
Press the required setting.
Press OK.
Press the required Wi-Fi network.
Press Password.
Press Enter password.
Key in the password for the Wi-Fi network and press Done.
Press CONNECT.
Press the Home key to return to the home screen.