Social Sites
I would go the C&F route. But be more of an celeb jack ass. As people on these sites tend to have inflated egos and they think they are a "celebs". So you pretty much have to do the same or else you may not go anywhere. On sites like mysapce where you can customize the looks of your profile, it is best that you do as it allows you to show off your personality. I will say it is best not to over do it as no girl really wants to wait 5 minutes for all of the junk on your page to load.
Also fill out as much as you can on your profile. I say this as who knows what you may have in common when some girl views your profile. Lastly if you are going for a specific type of girl, it being a cougar, party chick etc, it would be best to tailor your profile for such girls.
Dating Sites
With these sites I would go more for the personality route than anything else. But throw in the C&F without the huge ego thing of the social site. I would also throw in a DHV "story"* or two. Do not do the sweet and smooth thing because just like the cocky BS girls are also fed up with guys being smooth. Girls on dating sites for the most part want guys to be real and themselves. I know that sounds AFC, but think about why the girls are there in the first place. They are there to get dates which may lead to a relationship. They don't wanto to deal with the big egos or the players (ie the smooth guys not pua's
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And like the social sites if you are going for a specific type of girl tailor your profile for that type of girl. As well as fill out as much as the profile as you can. You may want to even go as far as to vaguely describe what girls you want. I say vaguely because if you make it to specific then you may miss a great girl to date and have a relationship with.
*What I mean by "story" I really mean item. I am talking about mention that you have traveled and maybe mention a couple of places where you been. Or toys you may own. Or even hobbies that you take up. Basically dhv by showing what activities you take part in.
CHAT