1) Prime black and basecoat your gold sections in Bestial Brown. This doesn't have to be a perfect coat.
2) Add several thin layers of Dwarf Bronze. Metallic paints tend to have odd textures when layered on too thick. Be patient and don't use TOO thin of a mix of paint or else the glitter will separate from the binder and pigment of the paint.
3) Using a 1:1 ratio of Burnished Gold : Dwarf Bronze, add several thin layers to your metallic sections.
4) Paint several thin layers of pure Shining Gold
5) Mix a 4:1 ratio of Burnished Gold : Mithril Silver and apply to your higher sections, leaving the lowest recesses pure Burnished Gold. The goal is to lighten up the gold to really pop.
6) Mix a 1:1 ratio of Burnished Gold to Mithril silver. Highlight the parts of the model that will reflect in the light. For a more advanced technique, use the same principles of non-metallic metals using metallic paint.
7) Highlight with pure Mithril Silver for that super polished effect.