Step 1. I have began by putting the Brown Pigment into a container and mixind it with water to achieve almost fluid-like consistency.
Step 2. I applied the watered-down Brown Iron Oxide pigment on the bike's wheel. Try to apply it on the highest parts and dirty up the wheel's plating a bit as well it will look more natural.
This is the end result...
I would also like to invite you to the Den's Facebook page. It's easier to receive new updates on new tutorials and painted miniatures.
Feed your Imagination,