The CMV Transmission and Immune Tracking (TransmIT) Study was developed to address critical gaps in understanding of cytomegalovirus (CMV) transmission dynamics in early education and care (EEC) settings. This two-stage, community-engaged study design integrates EEC center partnerships, digital study platforms, and data pipeline infrastructures to enable longitudinal virologic and immunologic surveillance in this high-exposure environment. Stage I focused on establishing foundational components of the study, including a geographically diverse EEC center network, culturally tailored recruitment strategies, a community advisory board, protocols for participant enrollment and saliva sample collection, and optimized laboratory assays to measure viral shedding in saliva. The study approach honed during Stage I is intended to support future longitudinal investigations into viral shedding patterns, immune responses, and co-infections among children and staff in EEC centers. This manuscript presents a methodological framework for conducting community-centered scalable research in early childhood settings with relevance for CMV and other infectious diseases of public health importance.