WatchOS 3 has been released by Apple and it comes with some major updates. This release is the biggest since the Apple Watch came out. watchOS 3 improves both the speed and functions of the Apple Watch. You can download the latest update for free, however your iPhone will need to be running iOS 10.
To install, make sure your Apple Watch have been charged to 50% or more. Also, confirm that your iPhone is on iOS 10 then navigate to General > Software Update in the Watch App on your iPhone. That’s it, leave it to run. Expect it to be a little sluggish because a lot of people will be hitting Apple servers to update their devices. So be patient.