I'm not a fan of air travel, and I've done far more of it than I ever wanted. Things that help:

Moisturise and hydrate, and consider your eyes and your sinuses as well. Get the type of eye drops sold for people with dry eyes, and find a basic saline nasal spray (I use Fess, which may not be available in your location).

Noise cancelling headphones are good, but a pair of the basic noise-occluding plugs sold for use in noisy environments is also useful. Pharmacies usually sell them.

A good, comfortable eye mask.

A scarf - nothing heavy, but just something that you can wrap around your neck or wad up as a pillow.

I always travel wearing a ScotteVest, so that all my small items are in easy reach. Also makes getting through the security circus quicker.

I knit on planes: a small set of circular knitting needles and a ball of yarn will keep me calm for hours.