If you want to start using the Windows 10 Fall Creators Update before is officially available, you can jump to the new version in two different ways.
The Windows 10 Fall Creators Update (version 1709) is officially expected to start rolling out to compatible devices around the world on Tuesday, October 17, 2017, but it'll be a slow rollout that could take months before everyone gets it. However, if you're eager to start using the new version, you can download and install the Fall Creators Update even before anyone else gets it, using the Windows Insider Program.
Of course, the program is not for everyone, and there are risks of bugs and errors. Microsoft designed the program to allow enthusiasts and developers to test upcoming features during the development process, but now that the new version of Windows 10 is pretty much complete, you can install a pre-release with minimal risks.
You can install the Windows 10 Fall Creators Update before it's officially available in at least two different ways. You can become an Insider and configure your device to get the latest build through the Fast ring. Or it's also possible to enroll your machine in the Release Preview ring that allows you to get version 1709 (usually) a few days before the official launch with a very low risk of coming across issues.
Full story from the WindowsCentral blog...