There are many digital transformation challenges going forward towards Industry 4.0 in Thailand, especially for the traditional manufacturing firms that have been operating without digital technologies. The paper presents a case study of a safety shoe manufacturer, CPL Group Public Company Limited, adopting digital technologies to transform its production system of 40 years. It presents a conceptual design for production tracking based on IoT technologies for productivity improvement. This research uses inductive case study research design by interviewing executives and participating in the digital tracking development project using IoT sensors and image processing. The findings show the key success factors of digital transformation in manufacturing, strategies required for development, and the conceptual design of the production tracking system.