spread a few layers of white paper on the stain, gently wipe, and then step on it. Repeat this step until the paper is saturated.
Coffee is soluble in hot water, you may give it a try
stir egg and glycerin, pour it on the coffee stain and then brush 2-3 minutes with a toothbrush, rinse with water after that.(for dry coffee stain)
firstly spray scarvenging agent or Mr. Wei Meng on the surpace, then brush with a soft brush and rinse it, then absorb the water with water absorbtion machine, finally rut it dry with a dry towel, don't use washing powder.
