Once you downgrade, you can create your own recovery media, and then upgrade again. You'll need to be plugged into a power source, and Windows 10 makes it painlessly easy to downgrade. You can do this by going to Settings, selecting Update and Security and going to Recovery.

The first option is to immediately downgrade to your old version of Windows. If you already upgraded to Windows 10 but don't have any recovery media available, there are two options you can take. You can create a recovery media on Windows 7, 8 or 8.1 by using a USB drive or a DVD, but you'll need to do that prior to upgrading to Windows 10. A recovery media is similar to the DVD that shipped on older systems. If you made a recovery media prior to upgrading to Windows 10, you can use that to downgrade in the future. If your system shipped with recovery media like a DVD that contains the operating system, pre-installed software and the necessary drivers, you can use that to recover your system. However, there are still ways to get back to the version of Windows prior to your Windows 10 install. Once you remove your previous Windows installation files, you won't be able to recover your system to the point just prior to your upgrade to Windows 10. In my case, that amounted to 16.7GB that I was able to reclaim, but this will vary from system to system.

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