I'm not in HR, but I get the applicants after they pass the initial HR screening.
When I interview, I'm looking for several things. They include:
Wear a suit. People who come to an interview in a sundress, slacks and blouse or other "dressy casual" outfits are knocked out of the running in my mind almost instantly. I want you to respect the position and want the job enough to dress for it. If you're not going to try in the interview, you're not worth my time to train.
Make eye contact and smile. Even if you're nervous, smile. I can tell you're nervous, but again I want you to at least try to look like someone the rest of my team is going to want to be around. I invest an enormous amount of time in creating a strong happy workplace, I need you to fit in well.
Use concrete examples. I really don't care about what you would do, I want to know what you've actually done. I'm ok with personal examples to support your skill set as long as it demonstrates that you have been successful in the skill in the past. It's the most realist way to predict your future performance.