1. Download ISO Image (For edition select Windows 8.1, language is English, and download the 64-bit version).
2. Open file location by visitng the Downloads folder in Windows Explorer.
3. Right-click on file, and click on Mount, which is one of the options that shows up on the pop-up box.
4. While still being in Windows Explorer, navigate to This PC. Find the new drive that looks like you just insterted an installation DVD. It should have the Windows logo on it. Open it up by double-clicking on the drive.
5. Once you open the drive, find the file called setup.exe, once you do open it. This now starts the installation process.