The biggest improvements I have experienced:

- Noise cancelling headphones - so necessary 🙏🏼  Earplugs + noise cancelling headphones if there are kids crying nearby

- Water with added electrolytes (I make my own because most pre-mixes have added sugar, flavours, and colors. I just put 1g Redmond's Real salt, 1g potassium, 150 mg magnesium into a bottle and fill it with 1L water after security).

- I no longer eat airplane food, I'm the weirdo who brings my own food lol. Our taste buds are different up there and I didn't realize how bad it is until I tried it after landing. Also, I found that the combination of salty carb-dense airplane food + dehydration were the hardest things on my body.

Those are the top three things that significantly improved my flying experience, but here are a few other things that may help:
- In-flight drinks: Water or sparkling water only
- Isle seat to stand and walk every few hours
- Eye mask if it is a long flight
- Blue light blockers (in airports especially)