I did not take pictures for the individual steps but here's a tip for a good looking bug carapace.
The idea is to drybrush a couple of colors with metallics mixed in. Should take you about 5 minutes to get a good look.
1. Prime the model black
2. Mix your paints. You add either silver or gold ot each color to give it a slight metallic look. 4:1 ratio should do. I went with:
Naggaroth Night (dark purple) + Silver
Sotek Green + Silver
Warpstone Glow (green) + Gold
Moot Green (high pigment bright green) + Gold
Averland Sunset (ochre?)+ Gold
3. Drybrush these from the outside going in, starting with purple+silver on the edges and ending with the yellow+gold in the middle.
Here's my example.