I hate to recommend a specific product, but acronis works very well for doing that. I even prefer to have the system backup occur when the windows system is not running, so I use only the Bootable CD method. That way when the system will no longer boot, I just undo the same thing I had done, restoring the system partition image from an image file. the image file could be stored on a chip, or another disk, or even on a cd/dvd. I prefer that the image come from a disk like a "spare" disk.
If you have a WD (western digital) drive you can use the free WD version of acronis which has that capability, yet does not really have the rest of the capability that works with a system operating.
Like working with a paint program, it sure helps to have used and worked with any of the methods , prior to actually needing them. backup and restore a clean new instalation, see how it goes. With windows7 and UEFI and these additional partitions like recovery and system (actually the boot stuff MS calls it system) it can complicate the processes some.
With MANY of the cloning imaging or mirroring programs you can create a bootable cd or maybey even bootable flash chips to run the program that does the disk work. They have a minor operating system it boots to, which will get mouses keyboards and USB and optical devices working, really odd devices will not be accessable unless supported. Even hardware raid is supported with many of them.
Make the CD or Bootable flash to begin with, You didnt say you have no working computer that could create such a thing, or shoot an ISO onto a CD? So in reality all you need to find is any ol' cloning mirroring or imaging program that works from or is capable of creating a bootable media for which to run these from.
Be able to boot to said media as the first item, via either setting the bios to boot to it first, or using "boot menu" some motherboards have (via thier biosoftware) to quickly select a boot item prior to boot.
Many of the softwares also are simple Grafical user interfaces, so it is not like you need a manuel for typing in a bunch of weird commands. browse, select , check, go through all the options so it is set the way you want it. The only rocket science is getting things straight for the OS your cloning, and juggling the data, because your already Outside of the Operating system, If you could read/write the image then, you will be able to again outside of the system.
Fun Quote from me "The system is not working when you need to restore a system backup most, therefore the best system backup is done without that system."