Replying to International Flight tips/advice (26hrs to Melbourne!)

Hey guys, so I'm thinking there has to be a decent amount of people who have flown internationally and have endured LONG flights.

Details: Im heading to Australia for 10 days in 2 weeks. Three layovers, longest flight is from LAX to Melbourne which is 19hrs. I am booked in Business which they say has no in headrest TV and apparently no power sources for charging my laptop/cell phone.

Looking for tips or advice from people who have done 6+hr flights..

What to expect?
What to bring?
What you learned?
What you wish you knew?
HOW DID YOU SURVIVE THE LONG ASS FLIGHT!?!?!

Also if you have any suggestions on things to do while I'm in Melbourne pass them along!

Cheers guys!