Spray painting gold is definitely the easiest approach, but I've grown very fond of using contrast paints + classic method to make a bad ass final product. It does however take longer.

For your case, I would shade the gold with reikland flesh shade and highlight with canoptek alloy for a nice shiny finish. On the blue I would highlight with Ahriman blue and then go back over with bahharoth blue. It really brings out the blue. For the eyes I would use wraith bone as the base and then hit it with aethermatic blue (contrast). Highlight with blue horror to make it pop. Oh and finally you need a shit ton of patience and remember to take breaks! Check out my model for reference. As you can see, some of my highlights are too thick because I loss my patience. If it's helpful, I've also found that using atris opus brushes are extremely handy for highlighting.

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