Yes we are making lists again!
Make two lists.
In one list the elements of company cultures that you have experienced and liked.
In the other list elements of company cultures that you experienced and did not like.
So you may not have liked the bureaucratic approach in one organization, in another you valued their focus on training and development for example.
When you are done, circle those issues in BOTH lists that you feel honestly reflect YOUR company culture now!
This will help you reflect on the reality of your company culture and what you need to sustain and where you need to improve. There is a third list you can then create, what you WANT your company culture to be like, this will help define the goal you wish to achieve.
Of course this is just a starting point, employee satisfaction surveys are a powerful way to gain an insight to company culture.