You've gotten some good answers on this question, but one thing I
haven't seen mention of is consolidating the metal and drawing the hook
before turning it. To do this, place the scraper flat on your bench,
take your burnisher and roll it along the face of the scraper right
near the edge, while keeping the burnisher flat against the face. Make
a few strokes the length of the face, gradually moving just barely past
horizontal. Turn the scraper over and repeat on the other face.
I won't attempt to do the ASCII art here, put this produces an edge
that is shaped somewhat like a flat-bottomed "U" turned on its side.
(I.e., the metal at the arris has been drawn out past the edge.)
At that point, you can turn the burr the usual way. By drawing it
first, it should only take a few firm strokes to turn the hook. (You
shouldn't have to strain and sweat to turn the hook.)
BTW, the biggest mistake I used to make when turning the hook was to
make a hook that was much too big. A big hook makes it too aggressive
(good for scraping paint, maybe), and also forces you to tilt the
scraper too far forward to get it to engage. If you get it right,
you'll just barely be able to feel the hook.