Naps didn't happen for me either, but now I normally can get a few hours in at a time if I get home before noon. And if I get in first thing in the morning at an overnight, I can often times get three hours before I force myself up.
Everybody has their own strategy, and like I said before, some trips are worse than others. North-South can be tougher than East-West (which is odd because there is less of a timezone shift). For me there is nothing worse than flying all night and then sitting in traffic for two hours to get to a hotel. I can fly all day and then do that drive no problem though. Augmented crews help. Even if your break is only two hours (and at best you are going to get 90 minutes of sleep on that), it's enough to reset your body to get through. Cumulative sleep becomes important On off days I really try to get 8+ hours, so at least I am pretty well rested going to to a trip.
One of the biggest challenges for me is forcing myself to go to sleep/wake up at "normal" hours when I am at work. Lots of people subscribe to the "sleep when you need to" philosophy, but I really try to stay on whatever timezone I'm in. We have a lot of 48 hour layovers, so you really do have a full day and a half to go do stuff. For me that meant waking up this morning at 5am (because my body clock was about 7 hours ahead so it felt kind of like noon) and I'll probably try to stay awake until 9 or 10 pm tonight. Other people would have woken up at 3am and then crashed out around 4pm. Some people use melatonin to control their sleep schedule. It gives me terrible nightmares.
Really until you try it and work up some good sleep strategies you won't know how you handle it. And apart from the rest issues, pretty much everything else about international long haul is great.