How to Download and Install watchOS 4 on Apple Watch
Note: First off, you need to download and install iOS 11 on your iPhone. Second, your iPhone should be connected with a strong Wi-Fi network. And third, your smartwatch must be charged 50%; and keep the watch on the charger for successful installation of watchOS 4 on Apple Watch.
Step #1: Open Apple Watch App on your iPhone
Step #2: Tap on My Watch
Step #3: Now, tap on General
Step #4: Here you will find Software Update. Tap on it.
Step #5: Scroll down and tap on Download and Install.
Step #6: Here you will be asked for iPhone Passcode.
Step #5: Tap on Agree located at the end of terms and conditions page.
Step #6: To start downloading watchOS 4 you need to tap on Proceed.
Step #7: Now, Enter your Apple Watch Passcode.
It’s done! Once the download process is finished your Apple Watch will automatically reboot and you will be able to use watchOS 4. Now follow the on screen process to setup, you are all set to explore watchOS 4 on your smartwatch.