Another great Blender post from you! Btw, is Rigify good enough for serious production use? I and the people I work with have not tried it on our projects, but it looks like it could handle simple up to medium character movement complexity.

I don't rig yet in Blender and I only know how to rig in Maya and some other software that Autodesk decided to "kill". Anyway, I am starting to learn how to rig in Blender by watching YouTube tutorials from this Blender rigging expert named CGDive.

Here is his channel. He has a comprehensive rigging tutorial there, the title is Rigging isn't Scary.