Apple periodically releases beta versions of watchOS for developers and public beta testers, allowing them to try out new features and improvements before the official release. These betas are part of the Apple Developer Program, which requires a membership (paid). In addition, Apple sometimes offers public betas through the Apple Beta Software Program, which is free to join.

To install a beta version of watchOS, follow these steps:

1. Sign up for the Apple Developer Program (developer.apple.com) or Apple Beta Software Program (beta.apple.com), depending on whether you want to access the developer beta or public beta.
2. On your iPhone, open the Safari browser and visit the appropriate website (developer.apple.com or beta.apple.com).
3. Sign in with your Apple ID and agree to the terms and conditions.
4. If you’re in the Developer Program, navigate to the “Downloads” section and find the watchOS beta. If you’re in the Beta Software Program, follow the on-screen instructions to download the “watchOS Public Beta Configuration Profile.”
5. Download the profile to your iPhone, and then open the Watch app.
6. In the Watch app, go to “General” > “Profiles & Device Management,” and you should see the watchOS beta profile you downloaded. Tap “Install” to install the profile on your Apple Watch.
7. Once the profile is installed, go to “General” > “Software Update” in the Watch app. The watchOS beta should now be available for download and installation.

Please note that beta software can be unstable and may cause issues with your device. It’s recommended to back up your data before installing any beta software and to install it on a secondary device if possible.