Download the executable file and run it - no installation is required.
The executable file is digitally signed, and the signature must indicate :
"Akeo Consulting" (v1.3.0 or later)
"Pete Batard - Open Source Developer" (v1.2.0 or later)
If you create a USB bootable disk with a non-US keyboard, Rufus tries to select a keyboard layout that matches your system language. In this case FreeDOS, which is the default selection, is recommended over MS-DOS, as it supports more international keyboard layouts.
All versions of Rufus, since version 1.1.0, allow the creation of bootable USB media from an ISO (.iso) image.
If you don't have an ISO file, creating such an image, either from an optical disc or from a set of files, is easy. You can just use one of the many free CD or DVD burning applications, such as CDBurnerXP or ImgBurn.
To be completed !!