Series

I want to start some kind of fine art series, but I'm not sure where to begin.  I've got a few ideas bouncing around in my head.  Veins, anatomical systems, religion, iconic art.   I'm trying to muddle through how all of these fit together, or not.  Taking the first step and shooting is really what needs to happen, but I'm crippled by indecisiveness and the fear of failure.