Take your props off, unplug the esc servo leads going to your wkm, unplug the throttle servo lead from wkm to receiver, plug the new esc's servo lead directly into the throttle channel of your receiver (make sure signal wire is right way up). With radio off move throttle to top position, plug power into copter, now turn on your radio, you'll hear a series of tones, wait for the single tone THEN move your throttle to the lowest position, you'll hear another series of tones, done. Unplug copter, turn off radio, replug all wires into original places and check to make sure everything spools up nice and even, replace props, go fly.