Self-construction is the process of developing one’s self-image or sense of self. In Macbeth, Macbeth has to adapt his self-image from that of a loyal soldier to a strong king. Unfortunately, he does not develop into a strong king, but a paranoid one.
At the beginning of the play, Macbeth does not see himself as a king or even promoted. When Angus addresses him as the Thane of Cawdor, Macbeth gets angry and demands:
The Thane of Cawdor lives. Why do you dress me
In borrow'd robes?(115) (Act 1, Scene 3, p. 15)
He does not see himself as a higher rank yet. However, when the first of the witches’ prophecies come true, he begins to think that he has a future. He writes to his wife and she encourages him to take out King Duncan and take his place.
Macbeth does not develop into a bloodthirsty paranoid killer right away. First, he has his doubts. He has second thoughts about killing Duncan because he has been a good king and has done nothing wrong.
He's here in double trust:
First, as I am his kinsman and his subject,
Strong both against the deed; then, as his host,
Who should against his murderer shut the door (Act 1, Scene 7, p. 22)
Even after killing Duncan Macbeth is not quite comfortable with his role. He begins to hallucinate and have doubts. Instead of giving in to them, he develops both his paranoia and his tyranny. He sees threats everywhere, and kills Banquo and Macduff’s family in order to secure his role.
Macbeth draws much of his self-construction from the witches and Lady Macbeth. They manipulate him at every turn, making him a paranoid tyrant and killer.