Once the proper configuration profile has been installed from the Apple Developer Center, the new watchOS beta 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 5.1 includes support for the Group FaceTime feature that's also available in iOS 12.1 and macOS 10.14.1, with Group FaceTime calls able to be answered in an audio-only capacity on the Apple Watch. Group FaceTime allows you to chat with up to 32 people at one time.
The watchOS 5.1 update brings a full-screen new "Color" watch face option for the new Apple Watch Series 4 models, with users able to choose between dozens of shades. There's also a filled-in circular color option for older Apple Watch models that joins the standard Color clock face.
Alongside macOS 10.14.1 and iOS 12.1, watchOS 5.1 introduces support for more than 70 new emoji characters like face with hearts, red hair, gray hair, curly hair, super heroes, kangaroo, peacock, parrot, lobster, cupcake, mango, and more.
For additional details on watchOS 5 and what was introduced in the new software, make sure to check out our watchOS 5 roundup.