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.
No new features were discovered in the first two watch watchOS 4.3.2 updates, but as a 4.3.x update, it's likely to be minor in scale, addressing bug fixes discovered since the release of watchOS 4.3.1 and making other small improvements to the operating system.
watchOS 4.3.2 is likely to be one of the final updates to the watchOS 4 operating system. Apple has begun work on watchOS 5, which was provided to developers at the 2018 Worldwide Developers Conference and will see a public launch this fall.