Materialisation and tessellation

I started learning rhino vault recently and wanted to model a vault with blocks. I modelled the vault, but now I don’t know how to offset and divide it into blocks. I searched the sites, but they all seemed to skip that part. The main question I have is: how can I make blocks out of the surface the rhino vault gave me?

Here is the photo of my vault and blocks I want to get. (sorry for the quality!)