I was an MBB consultant for six years. I've been on the interviewer side of probably 200+ case interviews since then through my current role in corporate strategy, where we recruit heavily from consulting. Here's how I would approach McKinsey prep if I were starting from zero today.
Week 1-2: Framework foundation, but loosely held
Read Case in Point or Victor Cheng's material. Get comfortable with the standard frameworks: profitability, market entry, market sizing. But here's the thing nobody tells you. McKinsey doesn't want you to recite a framework. They want to see that you can build one on the fly. So learn the structures, then practice ditching them when the specific case doesn't fit.
Week 3-4: Live practice, not solo drilling
Find two or three people to practice cases with. Structured case practice partners, not just friends humoring you. Use prepconsult.com or similar case partner communities. Aim for one case per day, at least half with live partners. The thing you cannot replicate alone is the experience of someone interrupting your structure with a curveball data point.
Week 5-6: PEI stories
Three dimensions, two stories each: personal impact, entrepreneurial drive, working in teams. Six stories total. But do not make them neat. A story with no friction is a story that tells the interviewer nothing about what you're like under pressure. Pick moments where you were uncertain, where you pushed against the consensus, where the outcome wasn't guaranteed.
The thing people skip: the Problem Solving Game
McKinsey uses an Imbellus-based gamified assessment that shows up early in the process and is pass/fail. It tests systems thinking and cognitive flexibility under time pressure. It doesn't look like a case. Treat it seriously. There are prep resources; use them.
Honest calibration: McKinsey hires a specific type. Not just smart, but comfortable navigating ambiguity, communicating with confidence before certainty, and building relationships quickly with skeptical stakeholders. If that profile doesn't describe you, prep won't bridge the gap. But if it does, process discipline is what separates the offers from the near-misses.