Detergent and Rubbing Alcohol
Mix up a cleaning solution with one part rubbing alcohol combined with two parts heavy-duty liquid laundry detergent. Dip the stained area into the cleaning solution and let it sit for 15 to 20 minutes. Dish detergent or shampoo in place of liquid laundry detergent will work, too.
Rinse the cleaning solution from the stain and wash the shirt in the hottest water recommended on the shirt's fabric care label.
Look carefully to see whether the stain is gone. If not, repeat the step or try another stain-removal method. Don't put the shirt in the dryer until the stain is completely gone; heat will make an ink stain last forever!
Ammonia and Lemon Juice
Apply a heavy-duty liquid laundry detergent to the ink stain on the wrong side of the fabric, then give the shirt a rinse under cold tap water.
If the stain remains, treat it with a mixture of equal parts cool water, lemon juice and household ammonia. Rub the solution into the stain, then rinse the whole thing again.
Launder the shirt as usual if no ink remains. If a stain can still be seen, repeat or try another technique.
Try removing the ink stain with fingernail polish remover. Test an inconspicuous area first to be sure the polish remover won't affect the color. Moisten the corner of a clean, white cloth with the polish remover, then dab the stain.
If you don't catch the stain when the ink is still fresh, try hairspray. Put a clean cloth or paper towel under the stain, then squirt the stain with hairspray. Repeat until the stain disappears, then rinse.
If the ink stain is set in and nothing will remove it, bleach may be worth a try. Mix 1/4 cup of household bleach with a gallon of hot water. Soak the entire shirt, as the bleach will affect the color of the shirt, for 15 minutes, then rinse. Use bleach only when nothing else will work, because bleach will change the look of the shirt even more than an ink stain will.