Ships don't usually come out from a brand new factory/shipyard to look shiny and clean, soooo.... i decided to do a wash on my ship.
(the "weathered" versions are on the bottom/right respectively)
In order to accomplish this, you need to thin out your paint with some sort of solvent, in most cases, they're terpentine based solvents. I used an enamel black to thin out the paint to a water like consistency, and applied all over the ship.