The development of environmentally friendly software is not a trivial project. And, in order to determine how efficient software is from an energy point of view, it is essential to be able to evaluate the energy consumed when it is running. However, simply having measuring instruments that allow us to fully analyse consumption may not in itself be enough. To ensure that the results obtained are correct and appropriate it is imperative to follow the correct steps. This paper presents the support for the activities and roles required to analyze the energy efficiency of the software. A process has thus been developed to guide researchers in carrying out the software+IBk-s energy consumption measurements, from study design to analysis and reporting of results. This process is known as the Green Software Measurement Process (GSMP) and it ensures greater control over the measurements made, improving the reliability, consistency, and coherence of the measurements. It also ensures that the results obtained are comparable with other studies and facilitates the replicability of the analyses performed. To define the GSMP, we have followed the method engineering approach and we also have taken as our basis well-known approaches to software measurement and good practices related to green software that have been proposed by other authors. To support the systematic development, management and growth of our proposed process by using a standardized representation, we have chosen to use SPEM 2.0+ADs this has also allowed us to generate documentation in a standard format that is available to anyone who wants to consult it on the web. This contribution, we believe, helps software professionals to be aware that there are processes and tools to evaluate the energy efficiency of the software applications they develop. They can thus develop software that is environmentally friendly.