Highlighted Hair: Apply Pre-Clean Purifying shampoo to wet hair and lather. Allow to set on hair for two minutes and follow with a thorough rinse. Permed or Color Treated hair: Apply Pre-Clean Purifying shampoo to wet hair and lather. Allow to set on hair for two minutes and follow with a thorough rinse. Repeat this process a second time. Virgin Hair: Apply Pre-Clean Purifying shampoo to wet hair and lather. Allow to set on hair for two minutes and follow with a thorough rinse. Repeat this process two more times.