I am going to try dying mine with a variety of colors based on an older post that used pearl gray, beige, and blue (forget which one). Dying is done based on weight so an 8oz bottle of Rit dye might color 2 lbs of fabric to darkest shade at 30 minutes in 6 gallons of water. My goal is to test color using smaller swaths of similar fabric at different times but maybe only using a gallon of water each time. I did this a couple months ago with the three colors mentioned above but it came out looking too much like the ESB version of the jumpsuit (too much blue tint) and not enough beige--I think the RotJ version is much more beige/gray/grime than that blue-gray version from ESB. (I'll probably also convert everything to metric for ease of scaling). I made mine out of 100% cotton twill so its massively absorbent. Fortunately, when it gets to a color you like, you can pull it out of the bath and add it to the rinse to stop it or even go less on the time in the initial dye and if its not dark enough, do it again so you don't overdo it (which is what I am terrified of doing).