Planning for Requirements Engineering (RE) is essential for achieving project goals effectively. It involves defining roles, work steps, and transparent rules to ensure smooth cooperation among all participants. Linda and Jan focus on creating a rough concept and a decision matrix to support the choice between custom software development and a standard product. They emphasize the importance of planning both phases of the project, considering aspects like requirement categories, documentation, and stakeholder communication. The use of AI and specialized tools is also discussed to enhance the efficiency and quality of the RE process.