Developed a comprehensive workflow diagram for a To-Do List Management Program in the eunbi-kim/24_2_W_SeProj repository, focusing on visualizing end-to-end user interactions and system processes. Leveraged Draw.io for diagramming and XML for artifact storage, capturing flows for login, subject or course registration, and to-do item management, including add, delete, modify, and sort operations. The diagram also detailed display options for completed and important tasks, providing a clear reference for team alignment and implementation planning. This work emphasized system design and diagramming skills, enhancing project clarity and readiness without addressing bug fixes during the documented period.