The best way to prepare for a product manager interview is to get to understand what is going on in the organization or industry you aspire to work in. Most product manager interview questions revolve around how well you can execute and deliver with the team.
The web is flooded with resources when it comes to product manager interview questions. Complete preparation is imperative to cracking the product manager interview at any esteemed organization. The most commonly recommended book is ‘Cracking the PM interview’, besides ‘Lean Startup’ which is good for understanding how to build good products. These resources lay a good foundation on basics like how to come up with an idea, test or validate it, launch it into the market as well as make improvements in it.
Having said that, getting involved with the media or industry specific websites, LinkedIn groups, and everything else that would give you more insight into a particular industry that you are interested in would be more useful than bookish knowledge. This also helps you network your way into a product manager interview and be aware of what is going on in that domain, which in turn helps you converse and answer product manager interview questions more intelligently.
The most common questions asked in a product manager interview are closely related to your roles, responsibilities and responses to situations as a product manager. As an aspiring product manager, your resume too is a product for the company hiring you. Your task in the interview is to properly portray your product (your resume) in the market. In other words, you, as a product, are in the market for a job and your customer is your to-be employer.
While learning about how to be a product manager or cracking a product manager interview, you should also apply those things to yourself, including how you represent yourself while looking for jobs. This is basically the practical application of your theoretical knowledge gained from books, connections and other resources.