It is based on the Jake instructions.
Update: 2017-01-21: OpenJFX has updated build requirements
- Create a C:\dev\ directory 
 - Download and install Visual Studio 2013 Community 
- Download (it may be faster to download the ISO)
 - Install 
- uncheck all the options
 - or download AdminDeployment.xml to C:\dev\temp then start the installation with:
vs_community.exe /AdminFile C:\dev\temp\AdminDeployment.xml
 
 - Add the path to MSBuild to the PATH environement variable (required to build Freetype):
C:\Program Files (x86)\MSBuild\12.0\Bin
 
 - Download and install the Mercurial for Windows
 - Download and install Java 8 (for OpenJDK)
 - Download and install JDK 9 b150+ (for OpenJFX)
 - Download and install Babun, then use its package manager to install zip :
pact install zip
 - Download Freetype source (2.6.2) and extract to C:\dev\freetype-2.6.2
 - Download Gradle 3.1 (for OpenJFX) and extract it into C:\dev
 - Download Ant 1.8.2 (for OpenJFX) and extract it into C:\dev
 - Get the JDK's source
In the Babun console:cd /cygdrive/c/dev
hg clone http://hg.openjdk.java.net/jdk9/jdk9/cd /cygdrive/c/dev/jdk9 ./get_source.sh - Get OpenJFX' source
In the Babun console:cd /cygdrive/c/dev hg clone http://hg.openjdk.java.net/openjfx/9/rt/ jfx9
 - Build OpenJFX
In the 'DOS' console:cd C:\dev\jfx9
set GRADLE_HOME=C:\dev\gradle-3.1
set ANT_HOME=C:\dev\apache-ant-1.8.2
set JAVA_HOME=C:\Program Files\Java\jdk-9
set PATH=%PATH%;%JAVA_HOME%\bin;%GRADLE_HOME%\bin;%ANT_HOME%/bin;%USERPROFILE%\.babun\cygwin\bin
set _JAVA_OPTIONS=-Dsun.reflect.debugModuleAccessChecks=true --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.base/java.util=ALL-UNNAMED --add-opens=java.base/java.lang.invoke=ALL-UNNAMED --add-opens=java.base/java.io=ALL-UNNAMED --add-opens=java.base/java.util.concurrent=ALL-UNNAMED --add-opens=java.base/java.text=ALL-UNNAMED
gradle - Run the auto-conf script for OpenJDK
In the Babun console:cd /cygdrive/c/dev/jdk9
bash configure --with-freetype-src=/cygdrive/c/dev/freetype-2.6.2 --with-import-modules=/cygdrive/c/dev/jfx9/build/modular-sdk - Time for cooking
make images
 - Once done, open a new 'DOS' console and navigate to
cd C:\dev\jdk9\build\windows-x86_64-normal-server-release\images\jdk
check that java runs:bin\java -version
or for something a bit more visual:bin\jconsole
 -  To check JavaFX, 
in the 'DOS' console compile the sample apps:cd C:\dev\jfx9
set GRADLE_HOME=C:\dev\gradle-3.1
set ANT_HOME=C:\dev\apache-ant-1.8.2
set JAVA_HOME=C:\Program Files\Java\jdk-9
set PATH=%PATH%;%JAVA_HOME%\bin;%GRADLE_HOME%\bin;%ANT_HOME%/bin;%USERPROFILE%\.babun\cygwin\bin
set _JAVA_OPTIONS=-Dsun.reflect.debugModuleAccessChecks=true --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.base/java.util=ALL-UNNAMED --add-opens=java.base/java.lang.invoke=ALL-UNNAMED --add-opens=java.base/java.io=ALL-UNNAMED --add-opens=java.base/java.util.concurrent=ALL-UNNAMED --add-opens=java.base/java.text=ALL-UNNAMED
set JIGSAW_HOME=C:\dev\jdk9\build\windows-x86_64-normal-server-release\images\jdk
gradle apps
then launch:%JIGSAW_HOME%\bin\java -jar C:\dev\jfx9\apps\samples\Ensemble8\dist\Ensemble8.jar
 - hack!