I just walked a company through this process. They have a staff of about 35.
The first step in any cultural initiatives is bringing the truth to the surface. To be honest, many employees sense the reality in their culture, but until it's brought to the surface and articulated clearly, no change can happen.
Once your culture is clear to everyone, the serious question to ask is whether you all want to change. Then - and only then - can your culture become more agile, focused and innovative.
Step #1 - survey/collect everyone's view of the culture.
Step #2 - have a conversation with your team after you've collected the results.
Step #3 - as a team, determine whether the current culture is what you want, or whether you need to change.
Step #4 - start small and decide on one change that you can make as a team.
Step #5 - implement the change, celebrate the win if the change goes well, then focus on another change you can all make.
If you need some more insight into this process, don't be afraid to get in touch.