As soon as I get on the plane I change my watch the new timezone and then use melatonin according to that timezone. I find this really helps. Also I try to eat in the lounge before flying so I can sleep at the right times and not worry about when meals will be served. If take off is late at night at the destination, I don't wait for meal service, instead go straight to sleep. On ultra long hauls you can usually get a snack when you wake up to tie over to the next meal service.
Using the timeshifter app helps, but often my work schedule doesn't allow following it. I can only really use it if flying on a Monday so I have a few days to sync up.