Which garage for which terminal
Heron Garage: Terminals 2 and 4. Palm Garage: Terminals 19, 21, 25, 26 and 29 (with a shuttle to 29). Terminal 18: its own surface lot.
Your terminal is printed on your boarding documents. Lines can move terminals, so check again the week you sail.
Parking vs. a ride
For a 7-night cruise, port parking can approach $175 at the daily cap. A taxi or rideshare from FLL costs about $15–$25 each way, so a ride is often cheaper if you're flying in.