I have more than 3 years of experience as an internal interviewer and more than 2 years of experience in a preparation company.
I always follow the following approach
1. Understand how to structure the problem
2. Identify the pain points of the analysis
3. Perform calculations with a technique that minimises the potential mistakes
4. Sanity check your results as senior consultant
5. Summarize and communicate the takeaways using the Pyramid Principles (top-down thinking)
All in all, I have more than 10 cases that I used in my previous experiences to prepare candidates. I have a 70-80% success ratio to pass to the second round. I am looking forward to working with you