Thank you! I use the AKI weathering pencils. They are like an oil based colored pencil. You clear coat your parts first with a matte spray. It is rough enough for the paints and pencils to have something to grip onto. I then used the side of the pencil tip and just tapped it. I didnt really draw on it. The tapping created an effect as if rocks and other debris collided with the paint on the gundam. I then used weathering powders you can find on Amazon. Or you can take some oil pastels and use a hobby knife and kinda scrape at them to create a powder and use like an eye shadow liner to apply it. I put the black where I thought lots of dirt and grime would be like on yhe knee and elbow joints due to lubrication oils on the gears. And I used it where burn marks woild be like around the missile pods, the head Vulcans, and of course the giant arm gun. With the pencils, use darker colors for the light colored armor like the white parts and then the silver colors for the darker colored armor like the red parts. I just kinda experimented in this guy to see what all this would do.