I'd suggest people start with CQRS+Events before going to CQRS+EventSourcing.
In the first case, you keep however you were loading/saving your entities, and modify them to emit events as they mutate. Then you can play with sending those events to external systems, or using them to drive read-models for queries, etc.
In the second case, you go further, and "dogfood" those events so that they are the authoritative record of what the entity is at a given point in time.
In the first case, you keep however you were loading/saving your entities, and modify them to emit events as they mutate. Then you can play with sending those events to external systems, or using them to drive read-models for queries, etc.
In the second case, you go further, and "dogfood" those events so that they are the authoritative record of what the entity is at a given point in time.