WinToUSB (also called Windows To USB) is the best free Windows To Go Creator that allows you to install and run Windows operating system on an external hard drive or USB flash drive, using an ISO/WIM/ESD/SWM/VHD/VHDX image file or CD/DVD drive as the sour
This article covers three ways to create a bootable USB for Windows 7 from Windows 7 ISO files, including usign Rufus, Windows 7 USB/DVD Download Tool.
This tutorial shows how to use Rufus to create bootable USB in Windows 7 and install OS from Rufus USB. You can also try a free alternative to make Windows bootable USB.