I created this standard for my fiance's Chaos army.

Follow the instructions for a general idea how to do this stuff, but be creative and make a banner for yourself!

All cutting and buffing was done with a dremmel, but you could also use the right scroll saw or router.
The small and inside bits were done with a metal cylindrical cutter, and all outside parts with a fiberglass reinforced cutting disk. Buffing was done with a metal fiber brush.

The magnet will have to be glued on, as I tried welding one, and just ended up destroying it's magnetism. An earth magnet will work best, as it's supporting a lot of weight.

I strongly recommend a protective top coat. Doesn't matter if it's matte, satin or gloss, but whenever I work with chemicals in my art, this is a MUST. (I don't take chances on what might be left behind)

Patina Green is an art supply, and lets you do some really cool things with metal. Art and hobby stores will also sell things like iron and copper paints, which you can use this on.
You also don't want to use a good brush, or clean it in your normal water container. I suggest a paper towel and an eye dropper.
BUT IT IS A CHEMICAL - ALWAYS USE IN A WELL VENTILATED AREA
Material Safety Data Sheet - [link]