Recently, the paradigm of Network Functions Virtualisation (NFV) has emerged for the rapid provisioning and management of network services. It is based on the cloud paradigm and the virtualisation technology. The European Telecommunications Standards Institute (ETSI) has been actively defining the NFV framework, which includes several functional blocks for network service provisioning and management. The interfaces and the roles of these functional blocks are being defined as well as the artifacts they manipulate. However, the workflow defining the relations and dependencies between these different blocks as well as the successive processing of the artifacts throughout this workflow have not been specified. This is the purpose of this paper where we define an NFV standard compliant process for network service design and deployment. The process starts from the tenant network service requirements all the way to the network service deployment.