Customer journey mapping is a tool that maps out a customer's experience with a product or service from their perspective. It captures what customers do, think, and feel at each stage of their journey, including before, during, and after using the product or service. Creating an effective customer journey map involves setting a goal, researching customers, profiling a persona, defining the stages of the customer journey, mapping out the journey, and making changes based on insights. Journey mapping is useful for both new and existing products and services to better understand the customer experience.