Blot freshly spilled milk with several paper towels until they no longer absorb the liquid.
Dampen a white cloth with dry-cleaning solvent. Dab the milk stain with the cloth until the stain is no longer visible.
Pour 2 cups of cool water into a plastic container, if any stain remains. Add 1 tbsp. of clear dish-washing liquid, and mix.
Dampen a sponge in the mixture. Pat the lingering stain with the sponge. Continue until the stain is no longer visible.
Remove the soapy mixture from the sofa with a clean, damp cloth. Pat the sofa dry with a towel.