First of all, in case you have already met in person, there is still the chance that there might not be a connection for everyone. If that is the case, have something set up where you both know that the other person isn't interested (just in case). Other than that, as JandK said, the hardest part is getting the party started. At some point someone will probably need to say 'so, who takes off their clothes first?', 'lets do this', or something similar. Just be prepared to do that. That will and usually is the hardest part. Once over that hurdle, the rest comes pretty easily. Good luck and let us know how things went.