I would focus on the company's core values, mission statement, leadership team and products. Company culture is key to placing yourself in a positive, successful environment. Each of these categories contribute to a company's overall culture and value proposition for you personally.
The best preparation for behavioral based interviewing is to brainstorm ahead of your interview specific situations you have been in, in the workplace. These situations should include a time where you were successful on a team, or a specific project, a learning experience, how you reacted to negative feedback, how you provided negative feedback, etc... You should have an idea of the type of situational questions you will be asked based on the job description of the role you are interviewing for. After you go through the brainstorming session, determine what the situation taught you, what action you took and the result that occurred from that action. You can find many examples of behavioral interview questions online, and I provided a link here to also check out.
Think about your own experiences (volunteering, other jobs) and be prepared to give a STAR example of your experiences which match what the company says it wants. STAR stands for Situation, Task, Action, and Result.
Practice. Practice. Practice. Before going into any interview, make sure you have answers planned out for some of the most common interview questions
The best way to ease interview nerves is to practice!! Ask your family, friends, classmates (anyone you can think of) to conduct a mock interview with you. It may seem silly at first, but it will pay off in the end!
[K]now your resume and experience inside and out. Similar to speech anxiety, the nerves come when you are unfamiliar with the content. In an interview, the content is you.
Most interview questions are behavioral based - using your past actions to predict your future behavior.
Many such questions start out with phrases such as "Tell me about a time when you...", or "Describe the last time you..." Usually the thought process you went through, actions you took, when and how you realized the mistakes you made, and how you learned from them are more important to the recruiter as there are really no "right" answers.
The best part of a weakness is the opportunity to learn and grow. Now that you have acknowledged and accepted your weakness, you can work hard to improve yourself. Explain the steps you have taken and are currently taking to strengthen your weakness.
Bring a folder with paper to write notes on, a pen and a few extra copies of your resume and cover letter.
For an interview showing up 15 minutes prior to the time you are asked is appropriate...I have been known to arrive at the building an hour early (due to very fast commute, etc.) and then I find a place to have a bite to eat or a coffee and wait until the appropriate time to walk in the building.
How many questions did you prepare for your previous interviews? My recommendation is to come up with three times that amount.
Remember that your interviewer is human too, so be yourself & take your time answering questions. Take deep breaths & don't drink too much coffee!