I'm a very new diver, but just had the pleasure of my first drift dive yesterday. All the above advise is right on ie sausage, staying with your group etc. In my case, the current was the gulf stream off Jupitor Florida. Trust me, it is a gas. The gulf stream is very fast and strong which gives the feelings of flight with the added benefit of not working very hard as you ride the current. Personally, I thought it all quite easy. I was, however, diving with the instructor who certified me so I had the benefit of expert instruction.
I would add to pay close attention to the predive instructions from the capt. and divemaster. They are very familiar with dive, and in my case had accurate dive conditions. If down this way, I can recommend the Blue Tang for a safe and pleasurable dive experience.
Hope you enjoy your dive as much as I enjoyed mine.