Brilliant white on the cloak! Could you give me a painting guide?

Thanks!
Sure I can, I think I remember the colours. The cloak was basecoated with a layer of the old Astronomican Grey foundation paint. Then, Skull White was gradually added to the mix. I think I give it some 6 or 7 layers, each time adding more Skull White. The final layer was pure Skull White.
It does indeed sound like a lot of effort, and it is, but it's worth every minute I think!