The factory floor is experiencing growing automation, which requires thorough training for workers to adapt to these advancements. This paper presents a part of a research project focused on developing a training interface (TI) utilizing Augmented Reality (AR) for workers in the furniture manufacturing industry. The research adopts a human-centered approach, incorporating co-creation sessions with stakeholders and usability testing. The objective is to design an AR interface that aligns with user needs and preferences, thereby enhancing efficiency, user experience, and satisfaction. Preliminary usability tests involved twelve participants using a low-fidelity prototype and six participants using a mid-fidelity prototype. The findings suggest that a well-designed AR training interface, developed in collaboration with users, can enhance the training experience on the factory floor, making it more satisfactory and leading to better acceptance. Future work will focus on further refining the interface based on continuous user feedback and expanding the application to other industrial tasks.