Make sure both Apple Watches are compatible and updated to the latest watchOS
Open the Walkie-Talkie app on Apple Watch
Sign in with your Apple ID if prompted
Add a contact by tapping the plus button
Choose a contact who also has a compatible Apple Watch
Wait for the contact to accept your invitation
Open the Walkie-Talkie app again
Tap the contact name to start a conversation
Press and hold the Talk button while speaking
Release the button when you finish speaking
Wait for the other person to respond
Tap the contact again to continue the conversation
Turn Walkie-Talkie availability on or off from the app
Use Control Center to check whether Walkie-Talkie is available
Make sure FaceTime is enabled on your iPhone if Walkie-Talkie is not working
Ensure both devices have Wi-Fi or cellular connectivity
Remove a contact by swiping left on their name and tapping delete