Hello. Mini guide for NVIDIA HairWorks. + 3 official Nvidia Tutorial.
In order to have earned Hair Works in the Unreal engine 4, you need to download the source code of the engine with the integration of Hair works-a separate branch of NvPhysX / UnrealEngine
To download you need to link your account with git hub epic! https://www.unrealengine.com/ue4-on-github
Nvidia GameWorks integration. https://forums.unrealengine.com/showthread.php?53735-NVIDIA-GameWorks-Integration&p=305752&posted=1#post305752