Launch the Apple Watch app from your iPhone’s springboard.
Select General from the My Watch tab, then tap Software Update.
The app will contact Apple to check if a software update is available.
If a Software Update is found, ensure that your Apple Watch is nearby and connect it to a charging cable. Once the watch is over 50% charged, tap the Download and Install button on the iPhone, then tap the Agree button to begin.
The Apple Watch firmware will be downloaded to the device. This may take about 5-10 minutes.
Once downloaded, the firmware will be prepared and then installed on your Apple Watch. This may take around 10 to 15 minutes depending on the size of the update.
You will notice a progress dial appear on the face of the Apple Watch. The progress dial will complete a full circle twice then your watch will reboot to the updated operating system.
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