improve their timing and efficiency.
1. Learn or refine your double haul by casting on the grass, and taking the time to stop in between your back and forward casts to think about what you are doing.
2. Cast with only a few fingers (thumb, pointer, and middle) holding the rod grip to force you to increase line speed through the haul only.
3. Use only the top half of a fly rod to learn to haul more efficiently. String your line through the guides of the half rod. Since you have no handle, hold the rod with your pointer finger stretched along the blank.
4. Mirror the haul with the speed-up-and-stop of your rod. When you stop the rod, stop the haul. The longer you move the rod through the stroke, the longer your haul should be.
For more great tips, check out 1001 Fly Fishing Tips: Expert Advice, Hints, and Shortcuts From the World's Leading Fly Fishers (Headwater Books, 2007)