Ultramarines

I prime the model in Macragge as opposed to Black.

Base the entire model. You may have to do a few layers to get the desired coverage.

Black out pieces of armour that will not be blue

Begin shading the armour. Thin down heavily with water and paint into recess and panel lines. You can reapply MacraggeBlue if you go over in any spots.

Highlight a small bit out from the edges. Thin this down heavily also.

Fine edge highlight. Thin down heavily.