I've done it a few different ways for commissions of mine. This is a recent one I did... I used an airbrush with createx pearlized paints and I also thinned some citadel paints to run it through my airbrush.
I started with a Vallejo as the silver base, then airbrushed a thin layer of blue, then red, then a red-orange, then plain orange, then yellow, then gold. Then, I touched it up with my airbrush with black. Finally, the weathering was done with black acrylics and testors copper, and then sealed up.
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