The fact that you were able to secure an interview shows that the company has seen something of value in the CV you have submitted.
According to Neville De Lucia, director at Dale Carnegie Training Gauteng: "No matter what the circumstances are for getting the interview, it is important to note that securing an interview is only half the effort. Once the door is open, we need to portray our internal confidence and competencies externally."
The objective is for you to indicate how you are a fit to the potential employer's corporate environment.
Below are some key considerations before you step into the HR manager's office: