Cremeegg
Plenty of water - no alcohol - little food - and start working on NZ time as soon as you leave - then you will suffer little from jet lag.
Just to show that it works differently for some. My long trips are with average water - more alcohol than I have on the ground and average food.
I find that, on the ground, I have a very small capacity for alcohol and get tipsy very easily (it's cheaper!!) but in the air, I drink more and NEVER get tipsy.
Lastly, I stay on the time zone of departure until arrival. I change my watch whilst we taxi to the stand. For me, jet lag is often more to do with my overall tiredness at the start of the trip, rather than how many zones I am going to cross.
I have tried the opposite way (as you describe above and almost everyone recommends) but I found that it did not change the experience of jet lag at all.