I started out with a pair of simple suede ankle boots (by Steve Madden, not that the brand will affect the project any, but if you were wondering where to acquire such a pair as this).
Next, I cut out the gear shape templates that I'm going to use to design the boots. Gears are very steampunk, and it's easy to find templates to trace online. I didn't pick anything fancy because, as you'll see in upcoming steps, I have to do everything by hand. I don't have the patience for meticulous activity.
The gears are laid out over top of the boots and I traced around them onto the suede with a fine tipped Sharpie pen. I did each gear one at a time for better alignment and variety. As you can see, I only wanted to design the toe and the heel, aka the parts of the shoe that won't bend as much and therefore won't crack the paint so easily.
The gears are all hand painted, very carefully. I used poster paints (part cheap store brand black, mixed in with Martha Stewart brand gunmetal gray). While I painted, I kind of smooshed the paint into the suede with the brush, if that makes sense. It took about two coats.
As a finishing touch, I glued feathers to an old button (which had been glued to a piece of metal I found in my mom's button tin) and then I affixed that whole contraption to the boots with Liquid Fusion clear urethane adhesive. I didn't want to use regular glue because, since I'd be walking around in them and the suede would move and bend and bunch, I wanted something a bit more flexible that wouldn't crack and let the decorative fall off.