Welcome Kevin. Yes, "be yourself, up a few notches", contestant coordinators can smell phoniness.
Now, think of all those interview moments between questions when Regis/Meredith asks the player to expand upon some interesting tidbit about himself. Have something honest that would fit that, which you can present in your tape without it sounding like it came from left field, and tell it with honest enthusiasm.
I hesitate to give an example, lest it be adopted without being based in truth, but this will give you an idea - I used a variation of it in the 1980s: "Being in New York for 'Millionaire' has an added excitement for me. I'm a huge roller coaster fan, and I've travelled all around the country riding all the major coasters. But I never made it to Coney Island for the great 'Cyclone'. As soon as I win, that's where I'm going to celebrate."
And if this were your tidbit, you'd need to know something about the "Cyclone" and a few other famous coasters, as well as the location of King's Island amusement park, etc.
Good luck!
Randy
tvrandywest.com