This is a cheap way to use crafts to make faux-metal pieces. I have used these methods to make armor that looks like real, decorated armor pieces, but is amazingly cheap and can be made at home with bare instruments for halloween, theater, or cosplay.
Things you'll need:
Knife/scissors, iron, hole-punch, paint brush
Paint, glitter, beads, other decorative items.
Jewelry is the main focus of this Instructable, but you can use the knowledge for crafting lightweight armor as well.
Step 1: Create the Design
Heck, if you're pretty good at tracing or free-hand drawing, you can create your own. Celtic knot designs work well for most jewelry or medallions. Dara likes to make 2 patterns, a blank cutting pattern for the bigger pieces and a clear marking or drawing pattern for jewelry she has to do multiple times. This works especially well for multiples.
Step 2: Trace/Cut Out Pieces
Iron on a metallic fabric to the craft foam.
Find metallic-shaded craft foam.
Choose generic craft foam, then spray paint it later. (This is the cheapest)
After you've chosen your method, cut out the design you've come up with. If it's one piece, you can use a soldering iron with a flat face to press in the foam to make it look overlapped.
Step 3: Decorating/Shaping
If you ironed on the fabric or chose an already metallic-looking foam, all you need to do is add paint to make it look older or burnished. If you just plan on painting everything that will come here in a bit.
You have the main form of it already, but to make it look crafted, you'll have to do some hand work. Iron over all the craft foam you're working on, and press down the sides to make it look like it was hammered or welded or ground into the shape you want.
Once you have that done, glue all your parts together (if there are any).
To make it look older, you'll need to paint it one way or another. Joints, recesses, edges, sharp curves, all could use a little dark paint that matches whatever metal you chose to make it look like. (Dark gray paint for silver metal, dark orange with a hint of green paint for bronze/coppery metals, bronzeish paint for gold, etc). If you want to make it look FANTASTIC, or just from fantasy, a few well-placed bits of decorative glitter help.
Step 4: Fasteners
Or velcro, you never know.
Step 5: Finish!
Now that you've finished your piece, you've finished your piece! Let it dry for a bit and you'll be done!