http://wccftech.com/update-macos-high-sierra-public-beta-to-gm/

If you are macOS High Sierra Public Beta user, then you will be pleased to learn that you can update to macOS High Sierra GM (Gold Master) build on your Mac.

Those enrolled in Apple’s Beta Software Program will be pleased to learn that they too can grab macOS High Sierra GM over the air right away. The update is available like any other software release over the air. If you wish to install macOS High Sierra GM right now on your Mac, then simply follow the steps outlined below.