This article explores the development of a comprehensive manual designed to bridge the gap between theoretical frameworks and practical applications in assessing mathematical Open Educational Resources (OERs). Drawing from the Erasmus+ Gate2Math project, the manual was created to guide educators in evaluating OERs using a streamlined, Google Form-based assessment framework. Its design prioritizes accessibility, clarity, and usability, offering step-by-step instructions, visual aids, and troubleshooting tips tailored to diverse educational contexts. By addressing common challenges, such as interpreting rubrics and leveraging assessment results for continuous improvement, the manual empowers educators to perform consistent and effective evaluations.

The study highlights the transformative role of such user-centered manuals in fostering systematic quality assurance, enhancing educator confidence, and promoting the adoption of high-quality OERs in mathematics. Feedback from educators during pilot training underscores the manual's utility, particularly in addressing the needs of users with varying expertise levels. The article further emphasizes the importance of involving end-users in the manual development process, balancing technical detail with simplicity, and maintaining adaptability to evolving assessment tools.

Beyond mathematics, the findings suggest that similar frameworks can be extended to other disciplines, supporting educators globally in achieving equitable, high-quality education. This work underscores the critical need for well-designed resources that translate complex quality assurance methodologies into accessible, actionable tools for everyday educational practice.

Keywords: Open Educational Resources (OER), Quality Assessment Framework, Mathematics Education, Manual Development.