Mud, it turns out, is a relative cinch. And unlike most materials, it's actually best to let it dry on a fabric first and then scrape off the chunks, rather than smearing it around. Then use an oxygen bleach product like OxiClean (use the powdered, not the liquid version) along with water, according to the directions, and soak the stained area. "Oxygen bleach can take a really long time to work the chemical reaction, though," Weiss notes. "You may have to soak it overnight – and you may have to re-treat." To speed up the process, she suggests combining the oxygen bleach with hot water, and let the item soak for a while. Whatever happens, don't let the solution dry on the fabric; make sure to rinse it first.