The main thing with the salt I think is realigning expectations and moving away from where your comfort zone may lie in freshwater fishing. That golden casting zone may need to move from 40' to 80' depending on location, fish and weather. You're also going to be using significantly heavier gear which will feel different.
If heavy gear saltwater casting is new and you have a holiday coming up, bear in mind that:
1) Your wrist and arm is going to get tired. You nees to practice and get used to the extra force your body is going to take!
2) You may not have used heavy lines and flies before- get ready to learn how to duck and that you rarely escape unscathed with the wind in your casting arm.
3) Per above it's probably going to be blowing a gale
5) I just had to put something here to be sure there was no four.
Learning to cast better and farther with light gear would be a useful endeavour and absolutely the way to go if you have time however if you don't I'd recommend some practice with the gear you will be using. There's a good chance shorter heavier heads will be the order of the day and these will help get your distance without having to learn how to cast like the comp guys.
Some one practical advice from me:
1) Learn to make your haul fast, it'll help reduce your rod arm fatigue greatly.
2) I'd recommend pullback in your stroke or learn how to comp style cast and flop the rod over, this works a dream.
3) Oval casting is good in theory but shit in practice, don't bother for long saltwater targets
5) In particular practice casting to targeta and leading targets. A slow moving fish is still fast in terms of casting. You need to be able to lead a fish accurately by 10-15'. Set up some targets in the park and get a buddy to shout which cast to, hit the spot in 1-2 false casts max.
6) Learn how to cast with speed - speed up your casting motions. Widen the arc, keep the loops good.
7) Learn how much line you can have between rod tip and fly when not fishing to make a fast cast. You want as much as you can control. You can hold the fly or leader in your other hand. I reckon you can push 20-30', nail this skill and you'll have no problem making fast casts to a sighted fish.
8) Line management is a pain in the ass. There's wind, there's surf, there's coral, the line will sink, the line will tie your legs together. But occasionally, in between swear words you'll get it in nice loops in your hauling hand or your stripping basket. On that point, get a stripping basket or make one!
9) Get some solid shoes, lion fish and cuts are no fun
10) Get some stripping guards for your fingers - the line cuts and it cuts good and deep.
11) Polaroids obviously
The final thing is that playing fish is very different and in particular the initial strLike. Do not strike! Bend the rod and strip strike with hauling hand!!! You'll have loads of line not on the reel at this point, control it back onto the reel allowing the fish to take it slowly whilst you brake it through your line hand, do not let go and try not to stop start. There is no rush heee though, watch for tangles. If you knot or tangle you'll probably lose an eye or two on your rod and the fish.
Next week will be a pictures FP.