If your sinuses give you trouble on long flights, pack a small washcloth in a resealable bag. Ask for a cup of hot water, dip the washcloth in it, and place it over your face. Breathing in the steam may help you breathe better.
You can also use that washcloth in the lavatory to freshen up before you land.
Also pack a toothbrush and toothpaste, some lip balm, hand lotion, and eye drops.
If you carry a refillable water bottle, you may ask the flight attendants to fill it.
If your airline doesn’t give you socks to wear, pack a pair to use when walking around the plane. Remember to pack them away with your dirty laundry so you don’t wear them until you wash them. No telling what’s on the floor…
Do you have trouble getting your ears to pop? Bring an apple. Then, about 25 minutes before you land…start eating it. The constant chewing will assist in popping your ears.
Candied ginger works for motion sickness.