I don't put my liner along the waterline either, usually, but only because it seems to come right off. I kind of rub it in right where my lashes are - not above or below. It definitely just takes PRACTICE! As for the blog, I think that link was just a post, but Amelia Liana does have a YouTube channel with several videos, including some that show her 'cheat' cat eye technique.
XO
Mandy