For U.S. users, in order to participate in the Galaxy Beta Program, you will need to download the Samsung Plus app. You will need to register for or sign-in to your Samsung account in order to complete this process. According to Samsung, both the Galaxy S8 and Galaxy S8+ are supported, but the Galaxy Beta Program is limited to Sprint, T-Mobile and unlocked versions of the smartphones.
Once you have the Samsung Plus app installed, you will need to navigate to Settings –> Software Update –> Download Updates to manually download and install the Android 8.0 Oreo update.
We should mention that although Samsung has updated its license agreement and FAQ, the Android 8.0 Oreo beta update is not yet available. We'll have to wait for Samsung to make the official announcement and provide the update via its servers.
With that being said, there are other signs that Samsung's Android 8.0 Oreo beta is right around the corner. According to SamMobile, the Samsung Connect and Samsung Smart Switch apps have both been updated to support Google's latest mobile operating system.
While Samsung is just not getting its toes wet with an Android 8.0 Oreo beta timeline, Google is already moving on towards an 8.1 release. Google released Android 8.1 Oreo Developer Preview 1 last week, and is well on its way to releasing Developer Preview 2, which will activate the Pixel Visual Engine.