PE firms have different interview Styles and methods however, most revolve around four different areas.

Background and personality this involves running through your CV successes and failures and strengths and weaknesses.

This helps the firm gauge how well you would fit in with their team and culture? Transaction experience detailed discussions around select deals. You have worked on in your previous job.

This would normally include both analytical and qualitative information about the deal.

The third area is technical knowledge.

Financial Accounting modeling questions as well as longer case studies that might have to be done within a limited amount of time.

Finally firm knowledge whether you understand what the firm or fund you're applying to is about and what you know about its employees and strategy.