Talk to everyone at your company! No, seriously, everyone. Whether you are just starting out or whether you are 6-12 months in, you should try and carve out at least 30 mins of time with as many people as possible. Ask what they do, listen to how they contribute to the business, and ask a few pointed questions, like "what is the company strategy", "what is the company culture", "where are the headwinds", "who are the inspirational leaders", etc. There is no better way to paint a holistic picture of an organization than by talking to the sum of its parts. Once you have that picture, go to work with your C-Suite team on ways to highlight and foster the good, and systematically course correct the bad.