Download Windows 10 Technical Preview. Microsoft has given direct links from their site for its new Windows 10. Windows 10Technical Preview expires on April 15, 2015
If you’re running Technical Preview, we'll send you notifications beginning on April 1, 2015 to remind you that it’s time to upgrade your PC to a newer version.
Windows Technical Preview may be substantially modified before it’s commercially released. Microsoft makes no warranties, express or implied, with respect to the information provided here. Some product features and functionality may require additional hardware or software. Important
The easiest way to convert an ISO file to a DVD is to use Windows Disc Image Burner.
Remember, trying out an early build like this can be risky. That's why we recommend that you don't install the preview on your primary home or business PC. Unexpected PC crashes could damage or even delete your files, so you should back up everything.
If you want to stop using Windows Technical Preview and return to your previous version of Windows, you'll need to reinstall your previous version from the recovery or installation media that came with your PC—typically a DVD. If you don't have recovery media, you might be able to create recovery media from a recovery partition on your PC using software provided by your PC manufacturer. You'll need to do this before you upgrade. Check the support section of your PC manufacturer's website for more info.
After you install Windows Technical Preview, you won’t be able to use the recovery partition on your PC to go back to your previous version of Windows.