What are small travel hacks that you wish you would have learned much sooner?

After traveling for many years I have developed a few small tricks that I wish I had known much sooner to have a more comfortable experience while traveling. I would love to have a list of other peoples small tricks as well, so please share your top learnings over the years. Here are 2 of mine to start the list of:

- If you bring your own water bottle to the plane, you can also ask the flight attendants to fill it up for you. This allows you to get a lot more water than just the small cups they hand out when they walk past you in the aisle. I find this very useful on long flights where you dehydrate quickly. Walking to the back of the plan with your empty bottle seems to work best and they pretty much always fill it up completely with water

- If you want to sleep on your flight during overnight travel, booking a low cost airline that does not serve any food or drinks is actually much better than the higher priced airlines that do. Serving first drinks, then food and then picking up the trash again causes a lot of noise and movement in the plane. And this also causes the other guests to use the restroom much more frequent, therefore creating a much worse environment to sleep on a flight. Therefore if I want to sleep I book a carrier that I know does not serve anything and just eat something at the terminal or airport lounge before takeoff. Then the moment I sit down in my seat, I just put my sleeping mask on and focus on having a restful trip, not worrying about any food/drinks.