I think it is important to not just talk about yourself. A lot of people simply list their achievements or qualities and think that is enough. You want to market how You can help the Company and what qualities or experience you have that will benefit both you AND the company. I would research the position you are applying for and know a lot of information about the company itself. I spoke to the person that hired me and they said that simply my knowledge and research on the details of the company showed interest and made me look passionate about the job.
ALSO, when answering questions, do not be afraid to take a moment, form your thoughts for your answer, and then speak after the brief pause. It looks a lot better to take a moment and speak cohesively than to respond immediately with a jumble of words. Good luck I wish you all the best! < 3