This workbook is intended to assist researchers, curators, and data stewards responsible for managing or developing metadata for data resources generated in biomedical or behavioral and social sciences research. It targets individuals with a skill level ranging from introductory to intermediate. Proficiency in developing effective metadata only comes with knowledge and practice. To achieve mastery, it is essential to understand the underlying concepts and theory, acquire knowledge of the data domain, be familiar with the relevant best practices, and hone your skills with software tools for working with metadata. This can be overwhelming for beginners, so to lighten the burden, this workbook contains core knowledge, tables, flowcharts, templates, standards, instructional videos, software tools, and self-assessments to help you on your metadata proficiency journey. The workbook is organized into three chapters covering: preliminaries on metadata, working with metadata, and specific metadata schemas. It has useful footnotes or links to further a journey into the study and application of metadata, a glossary of terms used in the workbook, supplementary technical references and training materials, and a list of acronyms. A beginner will grow confident working with metadata after putting this knowledge into practice. Please use related works to access video presentations and other related materials.