I have to disagree. Helping a girl throw a party won't raise attraction if she's the stereotypical jaded, "hot chick" who's used to guys fawning over her. But if she's intelligent and of only *gasp* average attractiveness, thus has to sort through less douchebags on a regular basis? Well, it's a different situation and will most likely find someone helping her out with no expectations to be a good thing. FYI, several of my best relationships (and by far the best sex) came when I had friendships that eventually developed into more. Try starting with a friendship and no expectations and whatever happens, happens. That's what I've found makes me happiest anyway. So if you're only interested in "scoring", well... then ignore this post. ;)
And yes, I've done lots of reading/studying on the subject (D'Angelo, Mystery, Tynan, etc.) However, I've found the women I'm attracted to just don't respond well (via experience) to a lot of what's proposed outside of some pretty obvious basics (have confidence, a sense of humor, and the ability to converse comfortably). YMMV.