I created this spitfire helmet to better understand the PBR workflow.
I started with creating a high and low poly version of it to bake the normal and ao map. The high poly models contains half a million poly, the low poly is only about 10k. After I was done with the modeling part I created the color, roughness and metalness maps and those are all done in photoshop using a brush, blending modes and phototextures.
I learned a whole lot with this project as it had some up and down moments where I really struggled with the PBR workflow. But in the end all of it came together and the leather came out almost as good as I hoped it would.