The design of problems is crucial for the effectiveness of problem-based learning (PBL). Research has shown that PBL problems have not always been effective. Ineffective PBL problems could affect whether students acquire sufficient domain knowledge, activate appropriate prior knowledge, and properly direct their own learning. This paper builds on the 3C3R problem design model, which is a systematic conceptual framework for guiding the design of effective and reliable problems for PBL. To help practitioners apply the 3C3R model, this paper introduces a 9-step problem design process. The initial steps guide an instructional designer through analyses on learning goal, content, and context to help select problems. Later steps ensure that the problem appropriately affords the specifications identified in the analyses. The last two steps incorporate a reflection component, as well as ensure the integrity of the 3C3R components in the problem. (Contains 2 figures and 1 table.)