First, capture the experience of several users with your product or service, so you can make informed choices about the map.
Map the experience for each user through time, moving left to right. What are the phases that they go through?
Once you’ve mapped out the basic journey, add in more detail using different rows:
What are the actions they take at each phase?
What are the emotional highs and lows?
What are people thinking and how are they reacting?
What channels are they engaging with?
What needs are being met at each phase?
Play with the map until you are happy with it. Use it as a working document and continually update it as you learn more through testing and research. Create polished versions to help you present your work.