Start with the job description. Mark the technical subjects, work settings and responsibilities in the vacancy, then prepare truthful examples that match them.
Relevant technical preparation for a Biomedical Engineer includes computer literacy, mathematical modelling, three-dimensional design thinking, prototyping, electronics programming and systematic troubleshooting. Communication, creativity and interpersonal judgement support Biomedical Engineer work with clinicians, patients and other stakeholders.
For Biomedical Engineer applicants, the University of Dundee identifies awareness of ethical, regulatory and safety considerations as relevant preparation. It also identifies understanding Software as a Medical Device as a relevant skill for Biomedical Engineer applicants, although the depth needed depends on the vacancy.
For each example, note the situation, your actions, your reasoning, the result and what you learnt. Keep the notes brief so that you can speak naturally.