You literally have 30 seconds to make an impression during an interview. This question should really be "how do I nail the interview and get the job" that is how critical the first 30 seconds are.
Looking at my diary over the past 10 years I have interviewed well over 1,000 different candidates in person. When I get that bad first impression they almost never recover. I now work for Betterteam (a hiring platform for small businesses) so have even greater visibility into what happens during that critical first interview.
So if you want to nail your introduction and the whole interview follow these steps:
1. Exercise on the morning of your interview
This does not need to be a marathon but 30 minutes of exercise will give you a buzz that will last most of the way through the day.
2. Be presentable
Other than clothing which is a given also check your appearance. This goes for ladies and gents. Use your phone to do a video selfie and check for boogers, spinach on teeth, lipstick on teeth, clumps of mascara etc. Nothing worse than spending an entire interview fixated on a booger hanging out of a candidates nose.