I'm 54, if we're taking a poll.
Anyway, I firmly believe in being yourself. Just be your best self. Aspire to be the person you want to be, and always be working toward that. That way, you can absorb and relate to those positive traits that you admire, and consider them part of yourself.
We all have certain charms and a sense of humor. When dealing with women, we have to be relaxed enough around them so that those natural attributes come out. I used to freeze up around attractive girls. I couldn't be myself, because I was too nervous. I was great around guys, and ugly girls, but if a pretty one came in I'd clam up. It took me awhile to get past that. To me, that's what "be yourself" means, being relaxed enough that your true personality shines through.
Now some people want to put on some sort of false PUA-based type of personality. That has never interested me because if a girl becomes attracted to me, I want her to be attracted to ME, not a false front that I'm putting up. I guess if you're just looking for a quick one night stand or something like that, it doesn't really matter.