One problem that many fly casters struggle with is knowing when to release more line. If you release too soon, the line moving up through the guides “unloads” the rod, causing your cast to crash to the water too early. If you release too late, you don’t have enough time to shoot before you need to start the backcast.
In this great how-to video from the Orvis Fly Fishing Learning Center, casting instructor Pete Kutzer explains two ways you can determine the right time to release the line–by sight or by feel. He also explains why proper line handling during the cast is so important.

I often have the line on my 8 weight wrap around my rod during the last half second of a particularly long double haul And it takes turns between wrapping in my fighting butt and on my rod between the grip and first guide
What am I doing wrong?
Am I feathering the line at the wrong spot or is my timing off? It only takes a second or two to fix but its still annoying
the angle of the dangle is proportional to the heat of the meat or the square of the hair.
They make it look so easy. IT’S NOT !!, BUT, it does get easier with practice. These guys have taught me a lot.