do you chat together online? have a few drinks (only works if you're both drinking, and don't get slaughtered, just take the edge off each other's inhibitions) and get a bit flirty and naughty. (disregard this if you're in a backwards country where 18 isn't the legal drinking age...) if you can't get her thinking about you sexually/romantically with a bit of bottled courage, you're basically shit outta luck. no drama, move on, try again with someone else.
>>2 has the right idea for anyone with whom you don't already have a friendship in the way