Once the proper configuration profile has been installed from the Apple Developer Center, the new watchOS 4 golden master can be downloaded through the dedicated Apple Watch app on the iPhone by going to General --> Software update.
To install the update, the Apple Watch needs to have at least 50 percent battery, it must be placed on the charger, and it has to be in range of the iPhone.
watchOS 4 brings three new watch faces, including a dedicated Siri watch face that displays dynamic information unique to each individual user. There are new complications for Now Playing and Apple News, and an enhanced Workout app that supports High Intensity Interval Training and new swimming options.
GymKit, new in watchOS 4, lets the Apple Watch interface with gym equipment for workout data sharing purposes, and the Activity app has been updated to provide intelligent coaching, monthly activity challenges, and tailored workout encouragement.
Starting a workout is faster than ever with a new Quickstart interface, there's a new look for Apple Music, and with under-the-hood improvements, third-party apps are faster than ever and can do more.
Apple plans to release watchOS 4 to the public on Tuesday, September 19, three days ahead of when the new Apple Watch Series 3 will be available to consumers.
For more on what's new in watchOS 4, make sure to check out our watchOS 4 roundup.