Unpack this zip file, put its contents in a directory called "Emacs" in your 32-bit Program Files directory. In this directory will be multiple directories, including a bin directory with all of the main executables. If you are running a 64-bit version of Windows installed in C:, Emacs binaries should thus be in C:\Program Files (x86)\Emacs\bin. Call this directory EMACSBIN.
Add EMACSBIN to your user account's PATH (or the global PATH) environment variables by going to System (right click on the Win8.1 start button on the desktop)->Advanced System Settings->Environment Variables.
Set your HOME environment variable to your home directory, e.g. C:\Users\<your username> using the same interface. (Just add to user variables.)
Your .emacs for customizations will be created in HOME. You can now type emacs at any command prompt. If you don't want your prompt to block, instead type runemacs.
To get Jade syntax highlighting, add jade mode to your emacs.