hook up to CO2, hook up a picnic tap, pour one pint to clear the trub. Purge the serving keg with CO2 by opening the pressure valve and connecting the CO2 to it for like 10 seconds. Take off the picnic tap, connect out to the out of your serving keg. (make a short clear tube with an out connector at both ends). This will fill you serving keg from the bottom, disturbing the beer as little as possible. when you see air in the transfer tube, stop.