Hi, you say that you are new to the long haul, so I'll pss on a few points, ignore as much as you like!!
If you think that you might want to move around, try for an aisle seat. However, the window does give a view! It's true that there is not much to see as you corss the pond but - clouds dependent - you'll see a lot of North America and the world looks very good from 37,000 ft!!
Wear loose clothing and check out the expected temp at your destination, as it might be cooler/warmer and you need to have clothes suitable. Travel in soft shoes. Your feet will expand during the flight - even with walking around and doing the exercises. Loosen the laces during the flight and then tighten to suit before landing. If you have slip-ons, they cannot give as much as you need them to. Your feet will return to normal within 12 hours (normally!)
Do not underestimate the amount of time that you spend standing in queues and so forth. I always carry a small bottle of water and a flapjack. If you are delayed in the lounge, there may be no refreshments. If you are delayed in the aircraft
before take off, then there are NO refreshments. They have to keep the aisles clear at all times when on the ground. I have found these simple precautions to be useful.
Don't forget to stop back and tell us how it all went. Also, this kind of question is normally better in Passengers & SLF but I'm sure it's fine here. (Looking out for low flying Mods)
