The idea here is to create a grind once that allows you to keep a micro bevel sharp for a long time afterwards with little effort. There are several possibilities:
You create a suitable hollow bevel by machine, which you then grind further by hand, or
You grind a slightly too small angle, which you then shape with a short micro bevel
actually, the pure freehand strategy is also a variation of the same plan.
If after some time the micro bevel becomes longer and longer or more crooked, you will have to start all over again.