I generally try to get about 6 hours of sleep scattered throughout the flight (several naps, basically). I then fall asleep pretty easily on arrival and get up around 5am. I usually plan on a 2 hour nap around 3pm day of arrival to stay up through dinner, but if you're just flying out Monday morning, I'd skip that.

The other common recommendation is to sleep several hours at the beginning of the flight, then stay up for the duration (basically forcing yourself onto HKG time right away).