Hello, Paul, and thank you for visiting.
The spinner and cowling chipping was fairly easy. First I applied a coat of Tamiya gloss black. Then, when that was dry, I applied a light coat of Alclad2 Aluminium. Next, I daubed some MicroScale Micro Mask here and there over the surface. When the mask had dried, the light blue paint was applied, then left to dry overnight.
The last major task was to gently peel away the Micro Mask. Don't be surprised if small bits of blue paint come free from the boundaries of the Mask. With that done I used a small piece of sponge to apply random mud effects. Don't overdue this step: when you know that you want to do just a bit more, STOP!
You'll be happy with the minimal effect. Now you might want to airbrush a little well-thinned mud-coloured paint here and there, but again minimal is all you'll need.
That's about all there is to it. Give it a try in future: I'm sure that you'll be successful.
Best wishes for all future success, and thanks again for your visit!