Find a quiet room with good cellphone reception, do not be on a speaker and use a good pair of headphones (for phone screens). While this might sound like common sense , it is surprising how many times candidates fail to do the above. If you don't have good cellphone reception in your area, talk to your recruiter to arrange for an alternative (Skype/BlueJeans etc.).
Spend time researching the company. A good place to start is the company's own website. Have a good understanding of what the mission of the company is and how it markets itself to its customers, investors and prospective candidates. Find out all the recent news about the company - most news reading apps will let you search for specific topics. Another great resource is the LinkedIn Company Page where you can get a ton of valuable information and find connections that you know at the company. Talking to current employees and learning from their experience can be invaluable while preparing for interviews. Other great resources include Crunchbase (especially for startups) and Glassdoor. For public companies, go through an analysis of their most recent quarterly investor conference call, as these can give insightful information on competitive trends, future outlook and key risks facing the company.
Have a clear narrative for your career thus far. Be ready to explain what you do to someone who might have very little (or a lot) of knowledge about your current company’s business model, industry etc.
Enthusiasm goes a long way. Build enthusiasm for the company you are interviewing with. Time spent doing research should hopefully help with this (if it does the opposite, then the company is not a good fit for you anyway). People want to work with people who will bring positive energy to the workplace and when you are genuinely excited about something - it shows.If you really want the job
Take a look at Glassdoor and Quora for commonly asked interview questions. Filter these by recency. If you have never been a PM before, the book ‘Cracking the PM Interview’ is another great resource. I found this book very helpful during my own job search after business school, despite having been a PM before.
If you know the name of your interviewer, look them up on LinkedIn. (If you are concerned that will come across as creepy, turn on private mode). Better still if you know someone at the company, ask them what this person works on and research that area in depth. People are more likely to ask questions related to their own areas of work.
Pay attention to recruiter calls. Treat your recruiter as a close ally in this whole process - your incentives are closely aligned (recruiters get paid for successful hires). Ask for guidance on what areas/topics the company tests its PM’s on. For instance a LinkedIn recruiter will tell you that we test for ‘Analytical Ability’, ‘Business Acumen’, ‘Consumer Product Mastery’ amongst other things. An Amazon recruiter on the other hand will tell you to go through its leadership principles in depth.
Practice with mock interviews. If you don’t have friends in a PM role, try using a platform like Evisors, where you can request a consultation with experienced professionals for mock interviews. I do consult occasionally on Evisors (my profile), but if you have an interview with LinkedIn, I am unfortunately unable to help due to obvious conflicts of interest.
Why do you want to work at this company? It is surprising how often people don’t have a clear answer to this question. I have heard people say ‘It is going to lower my commute’ or ‘I have been in my current job for x years and it’s time for a change’. While those are perfectly valid reasons - they should not be your primary reasons - at least not in a job interview. Do some research, find out which products within that company’s portfolio you like. Connect them with your background and experience and have a clear narrative.
Do you use our products? What would you improve? Again, time spent in research should help with this. If you haven't used any of the products of this company, try to talk to someone who has. This might be harder for enterprise products, but for consumer products there really is no excuse to not have spent time familiarizing yourself having an informed point of view. For enterprise products, it might help to go through B2B review sites like G2Crowd, where you can get a sense of how a company's customers perceive its products.
What is one technology product that you really like? Why? How would you improve it? Try to pick something non mainstream. If you pick Facebook or Google, can indicate that you haven’t really done your research, and the bar for a really good answer with those products is also very high.
What is one product/project that you have worked on that you are really proud of and why?On the day of the interview, try to stay calm and look forward to having a good conversation with your interviewer. Avoid long monologues in your answers. When asked a question, take a few moments to collect your thoughts and avoid the temptation to jump straight in. For product design questions, don't make assumptions but ask clarifying questions.