Project-Based Learning (PBL) is a widely adopted pedagogy that ignites students' interest of a subject through the investigation of an authentic problem and cultivates their abilities of innovation and self-learning. Traditional PBL often involves a project of complexity and significant scale, which, under the time constraint of a course, is often difficult for students to handle and risks insufficient comprehension of the knowledge and negative impact on learning confidence. This paper proposes an incremental teaching project concept and its design strategy on top of the traditional project-based learning. An incremental teaching project is carefully designed for a Java Programming curriculum, based on which we discuss the dos and don'ts of applying incremental PBL to teaching.