Wearing a long-sleeved shirt may result in cuff stains, either from body oils or from brushing the cuffs over dirty objects as you wear the shirt. Because cuff stains can be unsightly, especially in a light-coloured shirt, treat soiling as quickly as possible after you notice it. With pretreating efforts before general washing, you should be able to successfully remove stains from cuff sleeves and restore the neat and tidy appearance of your shirt.
Measure 1 tsp dishwashing detergent and 2 tbsp ammonia into the dishpan. Add about 2 qt. of slightly warm water to the dishpan and mix the ingredients well.
Place the shirt into the dishpan and push the fabric beneath the surface of the water completely.
Allow the shirt to soak for at least 15 minutes.
Remove a cuff from the water and rub an old toothbrush back and forth over the cuff stain to loosen the soiling and scrub it away. Repeat the same process with the other cuff.
Place the cuffs back into the warm water and allow the shirt to continue soaking for 15 more minutes.
Remove the shirt from the water and rinse it well with warm water to remove the detergent and ammonia.
Place the shirt into the washing machine and add an appropriate amount of washing powder. Add chlorine bleach to the wash load in a bleach dispenser for a white shirt or add oxygen bleach to the washing machine for a nonwhite shirt.
Set the washing machine to a warm water cycle and start the machine. Allow the machine to progress through the entire wash cycle.
Remove the shirt from the washing machine after the cycle finishes. Check the cuffs to make sure the stains lifted. As long as the cuffs appear clean, dry the shirt in the dryer.
If you suspect protein stains on the cuffs -- from food, for example -- use an enzyme pretreating product instead of the dishwashing detergent and ammonia combination. Allow the enzyme product to set on the cuff stains for 10 to 15 minutes and then wash the shirt in the washing machine.
Never combine ammonia and chlorine bleach because this combination will result in a toxic gas.