Act quickly when you're faced with an ink stain: Fresh stains are easier to remove than those that have set. Remove the garment and lay it on a clean white towel or paper towel, and blot the ink. Don't rub, as this will spread the stain. Blot as much of the stain as you can, transferring it from the clothing to the towel. After blotting away as much ink as possible, you will need to treat and soak the stain to eliminate any remaining ink. How you do so varies based on the ink color.
Red and Yellow Ink
For red-hued stains, the University of Illinois extension service recommends soaking the garment in a mixture of 1 quart of warm water, 1/2 teaspoon of liquid dishwashing detergent and 1 tablespoon of ammonia. Soak the stained clothing in this mixture for 15 minutes.
After a 15-minute soak, leave the garment in the water while rubbing the back of the stain. You can use your fingers or a soft-bristled toothbrush to work the back of the stain to release it.
Allow the clothing to soak for another 15 minutes. Then rinse it thoroughly.
Prepare a second bath for your clothing by mixing 1 quart of warm water and a teaspoon of distilled white vinegar. Soak the soiled garment in this mixture for 30 minutes and then rinse it.
Wash the garment as you normally would. Chlorine or oxygen bleach can be added to the wash if it is safe for the fabric you are washing. If the stain remains after washing, repeat this process again before drying the clothing.
Other Ink Colors
Pour undiluted liquid laundry detergent directly over the stain and allow it to soak in a bit before rinsing the garment.
Combine warm water with a color-safe or oxygen bleach to create a soaking bath. Read the instructions on the bleach; ratios of bleach-to-water vary, but, generally, the ratio is about 2 to 3 ounces of bleach to 2 gallons of water. Soak the garment for 15 minutes.
Rinse the bleach water out of the garment and launder as you normally would.