Hi there!
Basically, to prepare you can use some mock potential test for Bain, BCG, PST (McKinsey), or GMAT, and after every test just look into a solution to see where you have gone wrong. 3-4 mock test it would be enough for you to prepare for the potential test.
Here there are 3 fresh real-live MBB Cases from different offices in the Library. Try to solve them, I think, they will be very useful for you!
For Beginner level:
Laundry Chain – Revenue Increase
https://www.preplounge.com/en/management-consulting-cases/interviewer-led-mckinsey-style/beginner/laundry-chain-revenue-increase-215
For Intermediate level:
Grain Co-operative – Brand Launch
https://www.preplounge.com/en/management-consulting-cases/interviewer-led-mckinsey-style/intermediate/grain-co-operative-brand-launch-217
For Advanced level/the real one and used for final rounds:
Non-Profit Museum Revenue Increase
https://www.preplounge.com/en/management-consulting-cases/interviewer-led-mckinsey-style/advanced/mbb-final-round-case-non-profit-museum-revenue-increase-219
Have you tried to solve them?
What do you think - do you have any questions?
GB
Do you need any further help?
All the best,
GB