The development of communication and other soft skills among computer science students is not usually an easy task. Often, curricula focus on technical skills, with team projects being used for the improvement of communication skills. However, these teams usually comprise solely of computer science students. In this paper, we present a didactical methodology, called MIMI, which can be used in a short, intensive, programme for undergraduate students. This methodology has been implemented in real projects that have run annually since 2014. We advocate the use of team-based projects, with an important requirement that each team is both multidisciplinary and multinational. Additionally, the period of teamwork is short and intensive. A significant role in the project is given to team mentors. A mentor is a person, usually a university lecturer, who helps the team organize their work and tracks if the team's planned didactical results are being achieved. The program has proved to stimulate an increase of soft skills among the students who participated and, in particular, among the computer science students. The detailed description of our process will allow others to implement and build similar events in their university or company environments, the focus of which is a Multinational, Intercultural, Multidisciplinary & Intensive (MIMI) methodology approach.