The process is simple. We have tutorials on this subject. You have to create the splines or curves yourself (This is why in the tutorials the splines are already created) , Ornatrix provides ways to convert them to hair guides and attach them to the surface.
In this tutorial you can see how to convert the splines to Ornatrix hair guides:
https://ephere.com/plugins/autodesk/max/ornatrix/docs/6/Guides_from_Shape_Modifier.html
This is an updated tutorial about the Ox Ground Strands operator, used to attach the generated hair guides to the strands. Michael explains the whole process in a two part tutorial:
https://www.youtube.com/watch?v=w-Qhm7_Ff40
