Mod Podge is an art medium that may be used as a glue, as a decoupage medium or as a final gloss finish. It resembles white glue in texture but it dries clear, leaving behind a smooth surface. Mod Podge is especially ideal for children's crafts because it is easy to clean up. If you have spilled Mod Podge on the walls, clean it up as soon as you can.
Wipe down the affected area with soap and water applied to a soft cloth or paper towel if the Mod Podge is still wet. Mod Podge is highly water soluble, and this solution, if enacted quickly, leaves no sign of the substance at all.
Saturate the area by holding a soft cloth soaked in warm water to the spot for one to two minutes. After the Mod Podge has softened, scrape it away from the wall using a plastic scraper, like the kind you would use to scrape your car free of ice. Work gently and try to avoid chipping the wall's paint, as this can lead to the need for a touch up with matching paint later on.
Saturate the affected area using a steam cleaner if the Mod Podge proves to be stubborn. In the event that the Mod Podge has been on the wall for a while or if something has been attached to the wall for some time, a steam cleaner provides the heat and moisture that is necessary to pull the Mod Podge off. Be aware that after an extended period of time, removing the Mod Podge that has been attached to the wall will also remove the paint beneath it. The affected area will then need sanding and refinishing.