1. Download the Blitzwolf app on your phone, can be it Android or IOS and install your ZigBee Gateway eg. Blitzwolf BW-IS1.
2. Press the reset button on the device.
3. Open the gateway and press the "Add sub device" button and select the device.
4. Tap the "Confirm" button.
5. Select and enter the password for your home wireless network.
6. Wait for few seconds.
7. Press the "Completed" button, schedule as needed, or make rules to work with your other devices.
Works with Google Assistant and Amazon Alexa. Its use is almost endless. Here's a Google Smart Home demo: