Embrace simplicity even in your communication. Push out a culture of jargon, acronyms and puffed-up descriptions of things. Celebrate simple, effective communication. Your best people can explain to a child everything that your organization does. Your worst people are the ones who sound smart and official at the expense of being widely understood.
Simplicity is a very hard engineering challenge, but complexity compounds like interest over time. Without keeping simplicity, you will never keep up with competitors who are trying to disrupt you. Make sure your whole team knows this.