Needed to do something other than another spandex superhero sissy for the sake of sanity, so here's Echo splattered in glorious space mud.
Started with a clone trooper figure and wiped away the markings so it was plain white, then handpainted all the markings and visor. First used a dark blue, then went over it again with a lighter blue to create different tones, like the paint is fading. Then I used an emery board (really rough nail file) to lightly scrape at the paint to create the scratches. Used a drillbit and knife to create some battle damage, then made brown washes to muddy it up.