Ever have that feeling that a particular forum topic or problem was made JUST for you? one of those "my entire life has been leading to THIS MOMENT" feelings? Ok maybe that's a bit (coughsignificantcough) of an overstatement...
If you want a short fortune cookie solution: Be quiet, be courteous, and keep being quiet.
It sounds cheesy but being the guy with decent manners and the quiet smile seems to just break people's heads and they stick you in the highest category, or somewhere near it.
If you're willing to actually work on this and cultivate yourself to be able to function in higher society (good for you, it's rare to have that drive) then there's a whole lot more to it than using that trick to fake it at the few polite events you'll be attending involuntarily.
When you're in Classy mode everything you do has to be geared towards the goal of projecting that aura. You walk straight, you have a firm but not painful handshake, you speak in ways that put people at ease and impress them, and you show courtesy to everyone you interact with. Your dress, your stance, and your choice of personal hygiene will ALL affect how well that image is pulled off. You're generally aiming for somewhere inbetween Brosnan's James Bond and Cary Grant's... Cary Grant.
I'd start simple with the three basic steps to everything else:
1. Start practicing Courtesy. "Please" "Sorry" "Thank You" and "Have a nice <time>" along with getting the door, letting ladies pass first, and holding chairs should be practically muscle memory.
2. Ditch everything that leaves strong scent. Deodorants, soaps, everything. Subtle is better, and unscented/undyed soaps and deodorants tend to rely on actually working and keeping you clean rather than covering up smells. It's better for your skin anyway. Later on you might try a subtle scent and see if it works with what you've got naturally but for now pretend you've got allergies.
3. Start a
Wardrobe that fits your shape, and start
Reading even the gimmicky stuff. You'll need to seperate the wheat from the chaff a bit but there's worthwhile gems in there. Make some new
Friends with similar goals, everything is easier when you can draw on the knowledge of others.
A note on the wardrobe and hygiene: This isn't terribly expensive. My soap is the cheapest at costco, my deodorant is cheaper than Axe/Tag, and my clothes are on sale from Target. Once you develop a good eye (or find a trustworthy shopping buddy that has one) you can really get good clothing cheap, and a waistcoat with a tie and dress pants is a lot cheaper than a full suit for basically the same professional image nowadays.
Get used to people calling you Sir, if you pull this off it's going to happen a lot more often.