as we normally meet at home and meet couples we have found the best way is not to let the other couple sit together as we have 2 3 seater couches.
Ideally the 2 girls sit together and when this happens we find that they slowly both kinda end up sat really close to each other and when that happens it only takes the slightest of things to get the action rolling.
Still wish we could find a quicker way tho as the suspence is a killer. lol