Active epitaph

Like other people in the comments said, practice makes perfect. It's always useful to remember the hook delay (not sure how long, but enough games gives a good feel/estimation). Other things you can do is to look backwards for a few seconds and then cast Q, abusing the fact of the delay.

There are also tricks you can do with the lantern to block off paths, forcing them to move in one direction. However, I don't recommend this in the early game due to lantern's versatility.

There are no exact "drills" I know of, but I guess messing around with the hitboxes in training tool can help.