What makes for company culture? Foosball tables and free lunch Fridays? Is it long hours before launch day? Flexible vacation times?
Too often, when people talk about company culture, they fail to differentiate between values and style. All of the above things are style. Working late, not counting hours, blurring social and work life--that's all how people work. That's not why people work. It's not what makes work meaningful or important. It's not only window dressing, but it can often mask serious culture problems when companies need to deal with style differences as they scale.
For example, if you value working with the best people, you may find that the best people aren't all 24 year olds who can go out until 3am on a weeknight. Your culture should value a baseline of respect, dedication to the task at hand, open communication and quality such that the best performers can thrive no matter what their style.
Values are created by words and actions, by the choices the top people in the company naturally make. They underly every single decision.
Style is a function of activities. Style is either created by rule, programming or just left to happen organically through the whim of the behaviors of your first hires. Values are inherent to who you are.
People either strive for excellence or they don't, for example. You can't have Excellence Day on Fridays.
Be very careful not to let style be your culture, because it never scales and it optimizes for things that don't necessarily dictate success--like hours worked.