You will lose the ability to be in all the details of everyone’s projects as a team gets bigger. Instead, focus on setting a shared vision that can help everyone below figure out how to fit their work into a bigger machine.
Clearly setting and communicating priorities can be a good way to show how to practically apply the vision.
If you do get involved in more specifics it can be good to focus on the people and processes, rather than specific work. Build the best team and let them answer to specific questions.
Julie Zhou, The Making of a Manager