3. Be intensely private. Keep more secrets.
Don's persona is cloaked in mystery and intrigue. As a result, no one in his life seems to have even the slightest handle on who exactly Don is. When they were married, we hear Betty asking herself, "Who is in there?" while she watches Don sleep. The rest of the people in his life are left wondering the same.
"Draper? Who knows anything about that guy? No one’s ever lifted that rock. He could be Batman for all we know." Harry's words echo our sentiments. Don is intensely private. Just like his box of secrets he once kept under lock and key, we get the sense that a great deal of Don is hidden, and it's that ambiguity about his persona that merits intrigue.
Women hope they hold the magic key to his mystery-shrouded heart and men vie to be his confidant (remember Roger feeding him martinis and prodding him about his marriage?). Like Don's Right Guard slogan, the people around him want "any excuse to get closer" to the enigma that is Don Draper.
Play up the riddle of your personality by being intensely private and acting as if you too have something to hide (even if you don't) and the people around you will be entranced with the idea of unraveling the conumdrum.