Follow the criteria. There are so many people who forget to do this. You can literally see what the teachers are looking for in your work.
Let me give you an example. Let’s say you’re working on your personal engagement for your Biology IA. The highest strand says, “The justification for choosing the research question and the topic under investigation demonstrates a personally significant interest, or curiosity.” Well, then you make sure you do that and you make that clear for your examiner. If you find that your work makes that clear, then there’s not much that can go wrong.