Allright, first thing you'd want to do, is check so the neck is fairly straight. A straighter neck will allow for lower, smoother action, but can also cause string buss and loss of sustain. Hold your guitar upright and sight down the neck (sort of aiming it, like a rifle). You should be able to determine by looking at the edge of the fretboard if the neck has a bow, is straight, or has a back-bow. What you typically want, is a neck that is almost straight, with a tiny amount of forward bow. If it has back-bow or a considerable amount of forward bow, the neck needs to be adjusted via the truss rod nut. Adjusting it can be tricky, but generally: loosening the truss rod nut introduces more bow, while tightening it introduces more back-bow (or straightening it). Put a mark on the truss rod nut so you keep track of where you had it. Then, using the correct wrench, turn it about a quarter of a turn in the appropriate direction - not more. Now, retune the guitar and let it sit for 15-20 minutes and check the neck bow again. Repeat this as many times as nescessary. Note: Keep track of how many times you adjusted the truss rod, how far you turned the nut each time (and in which direction). This is very important if you decide you want to go back to your old setup. Also important: If the truss rod nut becomes hard to turn: Stop. You shouldn't have to force it.
Btw, some experts say you should do all truss rod adjustment while the guitar is strung up and tuned, while others say you should always detune the guitar first. I don't know which is right, but I would do it with the guitar tuned. If you prefer to detune it first, do so. Whichever way you do it, just make sure to retune it between each adjustment, so you get the correct tension over the neck.
Once you're satisfied with the neck bow, move on to adjusting the bridge or saddles. For a floyd, you need to adjust the height of the pivot posts (trem posts). These can be screwed in and out of the guitar body. Screw them in and you lower the action, unscrew them and you make the action higher.
IMPORTANT: If your floyd is a "licenced" copy, chances are high that it's made of cheap P.O.S. metal. If this is the case, you can ruin the knife edges or the pivot posts by adjusting the bridge while the guitar is strung up. I have personally ruined a licenced floyd copy this way. So my advice is: Don't adjust the trem posts while the guitar is strung up. First, try to figure out how much you'd have to lower the bridge. Use a ruler. Then detune the strings until they flap, unhook the trem springs (in the back of the guitar) from the floyd, and remove the floyd entirely (you don't have to take the strings off). Now you can adjust the trem posts to your heart's content without ruining anything. Use the ruler to see that the posts end up at a reasonable height. Then put the floyd back in (make sure it's seated properly against the posts), hook the trem springs back into the block and retune the guitar. Test play.
If you get string buzz and dead spots on the fretboard, you have put the bridge too low. Also check to see so the neck doesn't have a back-bow. Remember that you want a slight forward bow in the neck.
Btw, what guitar is it? I'm asking because guitars with rather rounded fretboard profiles (such as Fenders), tend to require more neck bow than guitars with a flatter fretboard profile - so you may want to keep that in mind.