Find Your Cruise
Where is your hotel?? Miami or FLL.
Normally transport to the hotel is provided but if this is not the case you can go by train and I believe coach but it is complicated to do that. FL is about 30 miles so a taxi will cost a bit. If you have a cruise only ticket I would suggest that you contact the Cruise Line and pay to use their transport. One other alternative is to hire a car for one day pick up in Miami and leave in F.L. Lots of options....Neil Dow.
Ps Would certainly recommend the Renaissance in 17SE St. and a fish restaurant near there called Kelly's Landing. Would also advise against using the Sheraton Yankee Clipper which is quite run down. For good hotel tips look at "Tripadvisor" web site and study the hotel comments...Ida Dow.
Taxi from MIA to FLL is around $65 plus tip. Or you can try a shared van hire from Tri Country Airport Express that costs $18pp. Or as Neil suggests do a one way car hire.