It's all relative, To me long haul is over 6hours I would say.
The Lisa Eldridge video posted upthread is my inspiration. Think of it as enforced me-time. Personally I like to tuck myself away by the window as I'm small and can curl up completely on the chair, also have very strong bladder so can time loo visits for when least disturbing for fellow passengers.
I take my hand luggage in an oversized squishy weekend bag, easy to stuff under the seat in front of me.
Comfy clothes - lounge wear style - so leggings/jeggings/yoga/harem pants depending on the look I want when I get there, top half in layers so vest/lose top/cardi/big scarf so I can peel off/layer on as needed. I take my poshest soft cashmere socks for during the flight. I don't care about padding round the floor in them - ignorance is bliss
. I make sure my footwear is easy to get on again and comfy for walking through airports and in case of emergency.
Beauty/pampering stuff:
Toothpaste/toothbrush - only been given this once, BA I think. Besides I have a preference for toothpaste and prefer a certain type of brush!
Micellar wipes to cleanse
Some kind of hydrating mist/spray
Lip balm
Eye cream
Hydrating eye spray
Hand sanitizer (I have a lovely dr bonner lavender one, has the added bonus of relaxing scent)
Hand cream
Deep moisturiser or even overnight mask type thing - I have an origins overnight mask that just looks like you've put loads of moisturiser on.
Light moisturiser with spf for before getting off the other end
Basic makeup kit for before getting off
I do drink lots of water. But will also guzzle as much wine as they offer me so I sleep well (depending on length/time of flight.... not so much fun arriving somewhere new drunk at 4am local time).
I have to order special meal anyway but it does always mean I get served well before anyone else. Always looks nicer too, someone has had to take time to prepare it. I take my own snacks as sometimes the selection they have isn't suitable for me. Do avoid anything with nuts in though for the sake of other passengers.
I take my own pillow and eye mask as it's just nicer than the ones they give you, if they give you any at all. Own headphones too and a book. I have never in my life had to wait whilst the staff sort my mattress out
I genuinely don't understand who the people are that can afford to travel like that! I mean normal flight tickets are so expensive. People who fly business/first class live in a different world to a lot of us, I feel. Wouldn't mind trying their world out though!
Good idea about the nasal/first defence spray. Shall add that to my list for next flight :)