As a general rule lines are designed to be cast up to the rear taper beyond the guides. The business end of a line is referred to as the 'head', which is comprised of a front taper, belly and rear taper.
If you let too much line out beyond the tip during the cast the lower diameter and mass (skinnier and lighter line) can no longer transfer energy effectively and the 'hinging' effect can kill the cast. When learning it's best to stick with the head in the air, and get as clean as you can with that. Make sure the rod matches the line, as that makes a huge difference.
With practice the line will tug forward at the end of the cast. Hold one big loop in the left hand (tightly) with the spare line between the hand and reel until the cast nears it's end, and let go allowing the head to pull the loop straight. There - you've just shot a little line.
Shooting line does not need to wait until the very end of the cast. Once the energy has established it's forward flight the running line can follow the head. That is to say, once the rod has un-flexed on the forward stroke the loop is in forward flight and running line can (potentially) be pulled along with it.
It's critical that no attempt to shoot (i.e. letting go of the running line) is made before the rod has un-flexed forward or the tension will dissapear and things will deflate like an untied balloon. Hold the line tight until the loop is in forward flight - and not a moment longer for most distance.
Once you get used to this, think about the tension leading up to release. Try pulling the line hand while the rod is flexing forward and you'll notice that the tension / load increases with a pull of the hand. Pull the line hand, holding the line tightly, away from the first guide (down or to the side, or both).
Now when you let it go the line will fly off the tip with much more vigor and speed when you let it go. This is a single-haul and a very effective way to increase power in your cast so it shoots further when you let it go.
Again make sure you hold that running line tightly whether you pull (haul) or not. Let us know how you get on.
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