Step 3: Patterning your armor
A solid project always starts with solid blueprints. There are numerous ways to go about getting these, and with videogames being 3D modeled in the first place, a savvy builder can extract game files into 3D models which can be manipulated in a ton of programs.
A friend of mine was able to pull the game files from Skyrim into a series of 3D models I could rotate and view in Photoshop. I used these to take still screengrabs of the armor from head-on angles, then traced the patterns into flat shapes in Illustrator. This took some tweaking; the initial blueprints I made were often too small when wrapped around a curved shape, so they needed to be modified here and there.
I have a duct tape mannequin I made of my torso which makes projects like this much, much easier to work on. After printing out a set of armor templates, I'd loosely tape the parts together onto the form to approximate the shape of the armor. If pieces needed to be adjusted, I'd make alterations to the pattern, then print out a new piece.
Paper is a good analog for Wonderflex. While Wonderflex can take some gradual compound curves, it generally doesn't like to make any sort of "dome" type shape without darting or trimming it in order to do so. In the first photo, you can see how the seam line in the middle of the chest allows an outward compound curve, since the two facing edges are convex shapes. If you can build elements like these into your patterns, you'll save yourself a lot of frustration when trying to shape the Wonderflex later on.