It's been quite a while since I've been that way but I doubt much has changed. It's really a pretty easy trip.
AOPA can help you plan it and get charts. Jeppesen has the best charts. Even if you're going VFR (probably the best in your equipment) a current Jepp enroute chart will give your frequencies etc.
Miami Center has some remote facilities in the Bahamas that will give you radio coverage much of the way even down around 8-10 thousand.
Survival gear is essential. You need a raft big enough for the number of people in the airplane. It needs to be placed where you have a chance of getting it out if you need it. It also needs to be secured so that it won't become a missile in the remote chance that you have to make a water landing.
Besides the raft, you definetly need life vests. Although uncomfortable, they should be worn while your flying. In a small single engine airplane (I guess that's what a Saratoga is ???), you wont even get them on before you're down if something quits. They're hot, they're uncomfortable, but it you want them to be useful, wear them.
Fly the island chain and most of the time you'll be within gliding distance of one or more small islands. I don't know what your range is, but if you have to refuel enroute, there are two places where you can. One is on the island of Great Inagua (a bit S of course about midway). Very limited facilites, but they have AVgas (expensive). Leave early, get there in the day. The other place is S. Caicos.
It's a pretty good stretch of open Ocean between Caicos and Puerto Rico and no land in between. If you are aprehensive about the over water stuff (I would be), the make Inagua your fuel stop. From Inagua, cut over and fly along the coast of Hispanola (the Dominican Republic). You'll still have some open water between the Eastern tip of Hispanola and the West tip of Puerto Rico, but its MUCH less than a straight shot from the Caicos (which if I remember is close to 500 miles). Once you get to Puerto Rico, it's a piece of cake into STT.
I suggest you plan to leave early enough to get there before dark if you're going to do it in one day. If you have to, you can stay overnight at Inagua or the Caicos.
Don't forget General Declarations (for customs and Immigration) if you plan to stop either at Inagua or the Caicos. Get lost of copies as you need them to get in and to get out. Get a set (departure) stamped by Customs when you leave Florida (any international airport).
I suggest one flight plan (filed in the US) that includes your stop and the down time for refueling. that goes as far as PR or all the way to STT. The islands aren't good about closing flight plans or filing them. They do the paperwork fine, but don't always tell anyone. You can update enroute by radio and close when you get there.
It you lose comm with MIA enroute, just find the Center freq on you Jepp and talk to an airliner. There are many flying the route and they'll be happy to relay position reports to Miami for you. That way they will always know where you are if you want them too.
It's not complicated, the scenery is gorgeous and the WX is severe clear most of the time. A good forecast will usually hold. If you can hold a heading, you'll get there .... the wind hardly ever changes much.
BTW you'll be smack dab in the Bermuda Triangle, but all the stories are myths.
Enjoy
