This why I am Single - Face Torque

Being a legend in my own timer, I think it's odd that I'm not totally aware of what my face is doing in photographs.  As in the picture above; I thought I was giving a pleasant "I'm happy to be where I am at this moment" smile.  Instead I got "I wonder what that itch on my calf is" flat mouth.  I thought the photo turned out well enough, left the great lighting & background, and moved on.  It wasn't until later, while filing the photo away on Flickr that I realized- I'm flirting all wrong!
Even though I'm a generally happy guy, I realized that unless I'm doing a genuinely big toothy smile or crazy over the top mouth-open gay smile, my face isn't doing what I thought it was.
All this time when I thought I was giving a guy a nice, friendly smile- no teeth, 'cause I'm playing it cool- I was actually giving them flat mouth nothing!  At least, I can be sure I wasn't giving them a frown, but instead of giving off a light smile that said, "Hi, I'm friendly and I think you're attractive, I'd sure enjoy it if you thought the same of me, "  I was actually giving them a look that said, "I breath. Fire good. Don't pee on me."
As a Gay of a Certain age, I have to give gravity its due.  I might have to admit I have a bitchy resting face, and actually have to work to make a pleasant smile.  Now, I'm afraid that I don't know how to gauge my facial muscles and will go in the opposite direction and start giving a crazy-ass toothy grin like a cartoon dog going nutsy for Beggin' Strips. This is not fun. How could something as simple as slightly lifting the corners of my mouth turn into a carefully calculated exercise in desperation?

Hopefully, I'll manage to get the right face torque to convey the appropriate smile, but in the meantime, if you've seen me walking down the street and our eyes met, I thought you were cute and I don't want to beat you up.