Joseph Flees.

MAT 2:13  Now after they had left, an angel of the Lord appeared to Joseph in a dream and said, "Get up, take the child and his mother, and flee to Egypt, and remain there until I tell you; for Herod is about to search for the child, to destroy him." 14Then Joseph got up, took the child and his mother by night, and went to Egypt.
19 When Herod died, an angel of the Lord suddenly appeared in a dream to Joseph in Egypt and said, 20"Get up, take the child and his mother, and go to the land of Israel, for those who were seeking the child's life are dead." 21Then Joseph got up, took the child and his mother, and went to the land of Israel.
Both calls, to Egypt and from Egypt, are recorded in the same format.
"Get up" - a call to action, to get moving. Do first, think later. Action before reflection. Not ready-aim-fire, but ready-fire-aim.
"Take the child and his mother" - companions for the journey, but also the purpose for the journey. You need to know why you are acting. In this case, because Joseph was responsible for the lives of his family and for the return of the Messiah to Israel.
This, the protection of his family, is Joseph's vision and purpose.
"Go to the land of Israel/flee to Egypt" - instructions for the task. A strategy. Mind you, they are very general instructions. Joseph and Mary would have had to find a place to live, work to do (doubtless Joseph's carpentering trade would have stood him in good stead), and the thousands of little things to learn about living in a foreign culture. God leaves all this to them. He has equipped them for the task and he does not intervene to disempower them.
Joseph even has the authority to adapt the instructions in the light of new information (that Archaleus was just as bad as Herod).
The best kind of leaders give the most general of instructions, leaving the rest confidently to the talents of those whom they have selected for the task.
"Because..." - reasons for the task. People always work better if they understand why they are doing something. The great lesson of army life for me was that most of the time we foot soldiers did not know what was going on. This was worst for us, of course, in the Citizen's Military Forces, with a general lack of commitment to the game and usually quite inexperienced officers unfamiliar with leadership and the need to communicate reasons to the troops. Many was the time we would simply be led from hilltop to valley for no apparent reason. At the bottom of this army, we never knew why we were doing anything.
God asks Joseph and Mary to do something big, and he explains the reasons why it is important. They gladly and quickly obey.
The best leaders will Call for Action, Communicate a Purposeful Vision, Outline a Strategy, and Give Reasons.