Block out areas with Spaceship Exterior . Use triangles or jagged structures. Cover about 40% of the model
Paint over blocked areas with Ultramarine Blue
Light Drybrush full model with Skeleton Bone
Pick out a few metal bits (guns, missile tubes) with Leadbelcher
Light Wash metal areas with Strong Tone
Paint base sand with Blood Angels Red , then a light drybrush of Skeleton Bone