Ok guys, I'm gonna give you guys the info I can give you right now.
While I was losing my virginity and plowing through this girls pvssy, I had a big giant grin on my face. The girl told me: "STOP SMILING!! BE A MAN!!!" So ever since then I stopped smiling too much. I felt sort of like I lost part of myself. See, when you're young you want to smile a lot or you'll turn into a scrooge.
Smiling is basically submissive behavior. I heard that for us as apes, it means "look, my teeth are not sharp, I cannot harm you".
I am a naturally happy person just like you OP, and I walk around wherever I go smiling, as long as there's something funny going through my mind. When I see my friends I always put on a big smile. See, most people have no purpose in life, they spend their days eating Dorito's and Lays chips.
Now, when it comes to smiling, I got my best advice from songs. If you listen to
this, you can hear the Kurupt say: Laughter enhances the chances of the killing.
Why is that? 'cause smiling faces deceive.
Then there's E-40 here in
Practice Looking Hard, at 1:25 he apologizes for not smiling to his friend.
It all depends on the context guys.
When you talk about a girls boobs, keep a STRAIGHT FACE. It's called calibration. Usually when I talk to girls I keep a straight face, in order for them not to know what I'm thinking. A big grin is usually a turn-off, unless something hilarious happens.
When I'm around people who I don't trust, but I don't want them to know about it, I'll put on a big grin. This way they won't know what I'm thinking. They might not trust me, but smiling I seem to come off more inconspicuously.
Laughing is a sort of a defense mechanism too. Sometimes people laugh when others get angry at them.
Then I went to the caribbean one time, and a friend of mine was rolling a joint, and he wouldn't take the grin off his face. Simply rolling a joint gave this man a 5-minute grin.
I live in the Netherlands where people complain 24/7. Nobody is like me here that they can just smile to themselves, except mostly foreigners.
When you're around girls you can smile, a smile is very attractive!! But you can't smile out of nervousness.
Written above is the long answer meant to show you different sides of the coin, but the short answer is this:
I saw a Tariq Nasheed interview on youtube (I couldn't find it right now), and he says that when you're talking to a girl it's important to keep a straight face in order for her not to know what you're thinking.
When you approach a girl it's like poker, you don't want to show your hand. That's why the grin is detrimental when you approach a girl, it comes off very nervous. Many people start to laugh and smile when they're nervous. So that's all you need to work on really. Don't grin nervously.