Pour 1 tbsp. cream of tartar into a bowl.
Add 1 tbsp. baking soda into the bowl.
Pour 1/2 tsp. lemon juice into the bowl, and stir all of the ingredients together.
The mixture should be a thick paste. Add more lemon juice if needed.
Dip a cloth into the mixture, and then rub it in a circular motion over the dye stain.
Let the homemade paste sit on the stain for about 15 minutes, and then rinse it off with water.
Apply the paste again if the stain is still there, and leave it on for 30 minutes the second time. Rinse the area thoroughly with water.