I really wanted to see a Gundam with gold joints, and luckily there was a demo version of Gundam available, so I used it to try out a color scheme.
The marker I used was yellow gold.
I was able to create a color scheme I liked based on the 78-3. ^_^
However, it looks less like a combat Gundam and more like a private Gundam for the wealthy, if you will. lol But I'm happy with it.

The trial version of Gundam can also be used for coloring practice. | みそしる定食's Gunpla works