Well it's good that you've already got a lot of experience catching fish and can obvisouly cast well enough to spot and catch a really nice slot red. I would say the easiest way to transition into catching trout on the fly would be to blind cast just like you would with conventional tackle.
The best flies to start with would be minnow patterns like Clouser Minnows or Deceivers. The size and weight will depend on the weight of your fly rod. The larger your fly rod, the easier it is to cast flies that have a little weight and size to them. Small lead eyes, on a longer minnow shaped fly (3" - 4") on a size 2 hook in your favorite color for the conditions will fish and suspend more like a Corky than a plastic on a 1/4oz jig head. Great strategy for fishing common wading depths. I would use an 8 weight (7 or 9 would also work well) for this kind of fishing.
I've also caught plenty of trout on 10 ft drop offs with a "sink tip" fly line and a more heavily weighted lead eye minnow fly. This combo would fish more like a plastic on a jig head. Fishing much deeper than that with a fly rod takes a lot of patience.
If you are fishing the flats in less than 2 feet then you probably won't need weight on your fly at all. The hook will be enough to get it down a little. This is a good thing as a lighter fly is always easier to cast than a heavier fly on any set up. But remember even hollow bead chain eyes on a Clouser are enough for the fly to fish hook up (#4) which is a more weedless presentation, whereas a Deciever always fishes hook down. If you are lucky enough to spot a trout before you cast in clear water I've had the best luck casting 5' or so in front of the trout and just past it, and tease the fly by a few feet away. They will come 5' - 10' to a fly they like whereas a Red more likely will only pounce 5" - 10".
The benefit to fly fishing for trout is that the lighter fly moves more naturally in the current than heavier conventional tackle which helps make up for the smaller bait that you are using. The other big benefit to me is in sight casting. I'd much rather have a fly rod in hand if I can see the fish because I know I can make a more accurate and delicate presentation. Sight fishing for Trout is normally much harder than sight fishing for Redfish or Drum. However the current State Record Trout was sight fished with a fly rod in the LLM and weighed over 14 pounds.
Give it a shot and post pics of your success!
Last edited by RedFly; 07-14-2012 at 11:39 AM.