I have gone through/am going through this. To be honest, it isn’t easy. The Ash documentation can be a bit spotty, although the Phoenix integration stuff is pretty good.
One thing I found helpful (if a bit intimidating) is the source for the AshHQ site. Reading it is eye opening, because it illustrates how the creators intended things to be used.
I keep thinking we need a book on the subject, but things are changing so quickly it would be difficult… 