Take some new toys as a treat for baby.
Make sure you definitely get a bassinet, we flew with Emirates and I phoned monthly to check booking and arrived v early for check in to ensure bulkhead seats and bassinet.
If there is a max weight for bassinet and baby is over that, lie lie lie 
I kept my watch on UK time and DH put his on Oz time to give us an idea of feeding/sleeping times but in reality DD grazed pretty much the entire journey and slept on random bursts.
Don't expect to get much sleep - DD preferred to sleep on me (sweaty/uncomfortable) and I worried she'd fall out of bassinet while in there do couldn't really sleep or concentrate on a film.
Bassinet excellent to sit baby in to feed, play etc and they love to have a good nosey at other passengers.
Accept all offers of help from staff and other passengers.
Try and get back into normal routine as soon as you arrive, DD was fab, we were not!
Enjoy the trip, travelling with babies is a doddle compared to toddlers...!