1. Open 
Messages.
2. Tap
at the upper-right corner of the phone.
3. Tap Device pairing.
4. Tap QR code scanner.
5. Scan the QR code shown on messages.google.com/web.
Messages.2. Tap
at the upper-right corner of the phone.3. Tap Device pairing.
4. Tap QR code scanner.
5. Scan the QR code shown on messages.google.com/web.