This resource outlines a process for choosing indicators aimed at assessing Open Research. The process relies on two concepts: an indicator framework and an indicator toolbox. The indicator framework is context-specific decision lens that sets out why, for whom, and under what conditions indicators will be used. Whereas, the indicator toolbox is the curated collection of potential indicators, qualitative and quantitative, organized and documented with the rationale for each selected indicator. The framework and toolbox work together. The indicator framework provides the strategy for selecting and using indicators, while the toolbox supplies and documents the chosen indicators and their application. This guide draws on the European Commission report: Indicator frameworks for fostering open knowledge practices in science and scholarship (2019).