As a proof of concept / promotional image, I did a REALLY quick paint job on one of the AotC style helmets.
Base paint is... stupid. So I painted it black first, thinking that it would be cool to have scratches show through like that. Not thinking that usually I'm using a base of primer for plastics. Well, the black didn't bond so well to the unsanded, unprimed helmet. That's issue #1.
Issue #2 was that I grabbed the Gloss White instead of Matte White (the aforementioned primer for plastics is what I usually use as the finish coat). So now I have a layer of years old gloss white on top of the black that isn't bonding.
So I sanded it down a bit, and put my matte white on. With all of these layers, I had orange peel, spots that wouldn't cover, etc... Whatever. It's going to be weathered anyway.
Grey is rustoleum grey primer. Black is more of the flat black that didn't bond to the helmet all that well.
Weathering is a mist of american accents fossil (a beige sort of color, the one I use on the back of an ESB Fett bucket), then acrylics daubed on like I did for Rex, but in shades of brown rather than greys. I went heavy on the rusty colors, in honor of Geonosis.
Visor is dark green, since that's what I had. You can't really tell even up close, so whatever.
Vents and teeth are cut out, and filled with black window screen and black nylon.
It's not padded for wearing... just a square of foam in the top to make it sit nicely on a stand. It could easily be made wearable, but I'm not planning to do that, so I didn't care much
So there you go, that's what one of these things look like finished up AotC style.