Samba is a free software re-implementation of the SMB/CIFS networking protocol, Samba provides file and print services for various Microsoft Windows clients.
First, this assumes that you already have OpenWRT installed. Read this article if you haven't upgrade firmware to OpenWRT.
Second, you must have a working USB flash drive attach to router. Read here for installing USB flash drive.
FTP is a method of transmitting or recieving files across the Internet and stands for File Transfer Protocol. This article guide you on how to enable FTP function on the OpenWRT router.
It is assumed that the router is flashed with OpenWRT. See this article if you haven't upgrade firmware to Openwrt.
WinSCP is an open source free SFTP client, SCP client, FTPS client and FTP client for Windows.
Most people use vi as the text editor during configuration of embedded device. I hate to use vi, in which I have to memorize all the commands. Whereas WinSCP is a GUI (Graphical User Interface) program where you can edit your file like notepad. Additionally you can use WinSCP to download and upload files including settings of permission.
TP_LINK TL-WRT1043ND router and OpenWRT is use in this tutorial.