Download and install the Linux emulator Cygwin from here (the small icon in the top-right corner). While running setup.exe, you need to install:
cmake, gcc4, gfortran, git, gitk, libX11-devel, libXext-devel, libXt-devel, libXt, libXext, make, m4, openssl-devel, perl, python, wget, xextproto.
Then download and build Hermes as described in the Linux section above.