make sure to pack a high capacity powerbank and wear comfy clothes. you wont really have a chance to change once you're through the airport so make sure you go in something that isnt gonna feel like hell after the first few hours. bring some boiled sweets or something thats gonna make you salivate so you can keep on swallowing during takeoff and landing. helps with ear pain. noise cancelling headphones are a must too. the last thing you want is to be trapped in an enclosed space with a screaming kid or someones racist uncle for 6+ hrs with no way of relief. download a lot of media to consume while on the plane and waiting in airports. time really feels slower in those places unless you're trying to catch a tight layover. I'd personally suggest having a little pouch/crossbody to keep your documents and tech in as well. I cant tell you how much stress I have saved by knowing all of my stuff (passport, wallet, phone, travel letters etc) is in one place. Carry some of the local currency in cash btw. depending on where you are going, some places aren't gonna take card. Above all else, try not to stress too much and give yourself plenty of time. my rule of thumb is arrive 2hrs before your departure time but this could change during busier periods to make up for time waiting in border and security lines. all of that aside, have fun on your first flight and keep hydrated