Cloud computing monitors applications, virtual and physical resources to ensure performance capacity, workload management, optimize future application updates and so on. Current state-of-the- art monitoring solutions in the cloud focus on monitoring in application/service level, virtual and physical (infrastructure) level. While some of the researchers have identified the importance of monitoring users, there is still need for developing solutions, implementation and evaluation in this domain. In this paper, we propose a novel approach to extract end-user usage of cloud services from their interactions with the interfaces provided to access the services called User-level Usage Monitoring. We provide the principles necessary for the usage data extraction process and analyse existing cloud monitoring techniques from the identified principles. Understanding end-user usage patterns and behaviour can help developers and architects to assess how applications work and how users satisfy with the provided services.