The final design illustrations for the Mk 45 Iron Man suit from Avengers: Age of Ultron. For the final model check out my good friend Josh Herman's page here: https://www.artstation.com/artwork/yD4WJ
The design selected in review.
This is how I'll start. The first job is to capture the pose, proportions and attitude before I even begin with designing it.
Final turnaround, what Josh used to build his model. A lot of the detailing and back view are worked out here.
Weapons and attitude thrusters in full deployment. I always try to suggest how these things should work, but they don't always end up in the movie as I envisioned.