I think it is press lock OR unlock twice, then put the key in and turn it within 20-30 seconds. What I believe that does is, the car receives the code from the fob transmitter, and ignores it, but remembers it, then it detects the transponder in the key and says, "OK, that must have been a legit fob, I'll let it work next time"
Assuming your key will start the car normally already.