Black shirts, and other articles of clothing, are particularly tricky when it comes to deodorant stains, as the white marks are even more conspicuous against the stark black coloring. You'll want to start with the same steps as the previous slide, and turn the shirt inside out and try to rub out most of the markings with cold water.
Once you're finished, instead of making a solution of water and baking soda, you'll want to mix water with white vinegar. Use one cup of water and two to three tablespoons of white vinegar. Let the mixture soak into the stain for about one hour, then take a clean toothbrush to scrub off the rest of the deodorant. Once this is done, throw the shirt in the washer and dryer, and the white markings should be gone.
