Kind of a dying phenomenon, honestly. Most people just send a fam request on Bloop or whatever now, and if you have enough clout she'll accept.

That said, back in the day my tactic was the ridiculously transparent compliment. Like, if she has giant breasts don't mention that. Find some part of her that sucks and pretend-compliment that. You'd think that would be obviously bullshit, but chicks are kind of dumb about it.