Contrary to its appearance, most of Stark's armors are not rigid metal suits, like a medieval knight's. His standard armor suit consists of approximately two million grain-of-sand-sized discrete units, which are shaped to have as large a surface as possible to optimize their effectiveness. The basis of the suit's structural integrity is the powerful force field which permeates the armor's "cells," as well as the whole configuration when active. Each of the "cells" is a tiny unit in its own right, contributing energy and computing power to the entire armor; this is also why the suit can remain functional even after having sustained considerable damage. The basic principle of the suit is holistic; each part contains the whole, as it were. When inactive, the entire suit can collapse on the microscopic level, the cells "folding" in on themselves to take up a smaller volume, like a three-dimensional accordion pleat.

While Tony Stark designs every aspect of the armor, the complexity of the design requires that production be entirely automated. Each cell is constructed by using specialized bacteria — the bacteria consume minute amounts of specific metals, arrange themselves on pre-tagged areas on the "chip wafer," then die, leaving a very small amount of iron, or gold, or gallium-arsenide. This method allows great precision in determining the thickness of circuitry.

All the details of the armor's construction listed above are laid out in the Iron Manual. However, some armor which appeared after publication of the Iron Manual may well use entirely different methods of construction.

Where is John Byrne's rejection of Iron Man, who kills innocent bacteria in the same way MythBusters killed innocent bees? IT MUST HAPPEN!

All you need is Ditko's cheat sheet, where he spelled it out for us:

BTW, did Ditko select the color scheme as well or did Stan order a more colorful, superhero-ish costume?

I did not know that.

Kirby designed the armor, right? Why are you putting that in quotes?

I'm asking because I'm curious how much credit Ditko deserves; most of the elements of that costume are from Kirby's original design anyway. Things like the lines on the chestplate and the triangular "ears" were abandoned in the next redesign.