You need to install the cloning software on the current drive.
You then save the image to another drive, either internal or external or even to DVDs.
If you have a large enough second internal hard drive you can partition it and save the image to the second partition but you must have it saved somewhere that allows you to restore it back to a hard drive ie not on the same partition.
The program usually makes a bootable floppy or a CD.
Set the drive that you want the image to be restored to as the master and then boot from whichever bootable media you created and then find the image and tell it where to restore it to.
Then when you reboot you should be in a working windows OS exactly the same as it was when you created the image.
Hope I have expalined that in easily understandable steps