The day flight is new, not sure if anyone has reported taking it LAX-HKG. You can search for lots of past threads covering your precise question (maximizing the CX F experience) and they are generally still valid. CX does stock catering more generously than any other airline that I have seen (more than SQ F, for example). There is going to be more food than you can eat no matter how hard you try. Some of the food highlights: caviar and balik salmon (from caviar house). Both are exceptional (this is not smoked salmon as you know it, but an order of magnitude better and quite expensive; you can buy it at many airports if you get addicted). The caviar isn't quite as good as it used to be, but that is understandable given the world supply situation. The "chinese chicken soup" kept as a snack and only served on request (generally not on the menu); simple peasant food, but amazingly good as a snack. The chinese teas, served chinese style (you have to ask or they will serve it English style). Excellent (and selling for USD 100 per pound in San Francisco). Good wines and cognac (Hennessy XO). And the list goes on. I like the CX playing cards but I don't like the ST pyjamas compared to what they had before (less stylish but more comfortable). Really too many good things in the CX service to enumerate, you'll just have to relax and enjoy.
Absolutely agree with Christep's advice on sleeping at the start of the flight; doing this is essential to adjusting to HKG time. I usually eat the caviar, go to sleep for 6 hours, wake up and then eat dinner and stay awake the rest of the flight (but my flights leave at midnight not noon).