The increasing requirement for businesses to disclose sustainability information digitally has prompted significant changes in the content and format of Environmental, Social, and Governance (ESG) disclosures. However, companies mandated to adapt to these changes face technological and information challenges regarding ‘what’ and ‘how’ to report. For European filers, the Corporate Sustainability Reporting Directive (CSRD) and its requirements, the European Sustainability Reporting Standards (ESRS), along with the International Financial Reporting Standards (IFRS S1 and S2), propose the use of the eXtensible Business Reporting Language (XBRL) as the anticipated technical solution for the digital data structure. The objective of this paper is to provide a methodological framework for effectively navigating the complex and interrelated concepts relevant to stakeholders. Rather than relying on cumbersome textual guides, this framework leverages an examination of existing taxonomies to offer readers insights into the essential glossary of disclosures and metrics considered crucial by official regulatory sources. Furthermore, the research discusses the emphasis on qualitative and narrative disclosures in ESG reporting and their feasibility of comparable results. Employing this methodology facilitates the implementation of corporate case studies and enables the analysis of mass amounts of future annual reports for comprehensive sustainability performance measurement.