Stain removal is all about speed and technique. Here's the proven method for tackling coffee stains effectively.
Hold the stain under cold running water from the back. This pushes coffee out of the fabric rather than deeper in.
Rub Power Wash detergent into the stain with your fingers. Let it sit for 5 minutes.
For stubborn stains, soak in a mixture of one part white vinegar to two parts cold water for 30 minutes.
Wash on the warmest setting safe for the fabric. Check the stain before putting in the dryer.