Well Olly James, you've certainly got a thread going, so that's a start! Well done!
But someone saying'say something interesting' is a good way to scare the epiglottis of any would-be socialiser, isn't it?!
In Australia I've seen your (current) approach work. Man ignores woman at bar all night then turns to her at closing time with "Right - you coming?" and she actually walks out of the bar with him, overwhelmed at her 'good luck'.
Being that straightforward in Britain on the other hand is likely to get you a slap on the jaw or an excess of undistributed testosterone.
Women decide. Therefore, let them do the chatting up. All you do is make it a bit easier for her. Make her feel special. Make her the centre of attention (but not too obviously). Entertain her with a bit of chat on the things she's interested in. Make her feel that getting into her pants is the last thing on your mind - or at least that it's never crossed your mind yet (make like you don't care). Make her feel interesting (she is!) When she starts to bite she'll let you know when you can switch on the part of your brain that says 'let's shag'.
Swinging as for dating. But with swingers you know they are comfortable about the subject of sex - but they still (generally) expect the same social courtesy. They might give you a green light sooner if you get on the same wavelength as they are on. Who know's?
Good luck. When you're young and pretty you shouldn't waste it by being a dufus ;-)
Theres no problem of finding a girl - trust me, there are loads there at university, Just none of them furful my sexual fantasy, a threesome.
Only asked! - probably wont get, but again! pm me!