Being cramped like a sardine on a flight to Hawaii can depend on the airline. If you're on a major carrier, chances are the seating will be a little more normal. I once flew to Hawaii on "specialty airline" with a great fare and it was definitely like a cattle car. I'm not a tall person and I could barely fit.

As soon as the plane takes off, reset your watch or PDA for Hawaii time and eat or sleep according to that schedule. You'll want to make sure you have small snacks to tide you over until the next major meal.

Ask for bottled water. No ice, if they offer you a cup. I almost always buy a bottle of water before boarding then ask the attendants for bottled water when they come by with the cart. That way I always have plenty of water.

I usually carry one book and some sudoku or crosswords so I can switch between them since I'm easily bored. I never watch the inflight movie because I like movies and would rather see it at home in its entirety with good sound.

Don't pack anything you know you will definitely need at your destination, such as medication. I travel coast to coast several times a year and have been lucky not to have lost any luggage, but I figure it's only a matter of time.

For whatever reason, I've not been able to work on my laptop during flight. I can never seem to manage to get the screen where I can see it and not cramp my hands up trying to type. Definitely carryon your laptop.

If you think you could nap on the flight you might get yourself a neck pillow. (The airlines no longer have pillows.) Little cat naps are often enough to be recharged...as if Hawaii wasn't enough.

Good luck!