1. Run the right program.
2. Tell it to make the image.
3. Wait till it's ready.
Notes:
1. Be sure that you know how to go back to the image if you need to.
2. It's even built in into Windows: http://www.pcworld.com/article/3011736/windows/how-to-create-an-image-backup-in-windows-10-and-restore-it-if-need-be.html
How is a system image created

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