small is the new big

Many small hallway conversations make large leadership.  After a hundred small acts, you can make a large act (if the situation demands).  It's rarely necessary to start leading with a "big speech" articulating how you're going to do things.  There are occasions it's necessary--mostly if you're taking over a highly dysfunctional team and already have the political will and firepower for the inevitable dismissals.  Short of that, start by a few dozen conversations.  Then a hundred.  Then more.  In these conversations you can also provide clarity and direction and correction.