It's always easy to choose a big bag, as you want to pack as many things as possible, but pick a reasonal bag. So here is a what in my bag - airport edition...
1) The most important documents - your passport and your tickets, put them in a place where you can easily obtain them when needed.
2) Separate your liquids. Put all the liquids into a zip lock bag - moisturisers, eye drops, liquid eyeliners... basically anything with the 'ml' or 'oz' label. Don't forget everything must be under 100ml/3oz or they will be thrown out during security check.
3) Wipes - I always take wipes, as you might want to wrap your face during the flight or your hands. They are an essential and you will find a way to use it, one way or another.
4) Spare Clothes - I always take spares clothes and undergarments. Who knows, maybe someone could accidentally spill their drinks on you during turbulence...
5) Water. This you buy once you pass security, as the plane journey is surprising dehydrating for your body.
6) My purse. That really a no brainer.
7) Food. I always take a sandwich or some crisp or maybe a sneaky chocolate bar, as airplane food is never yum.
8) Something to read. A book, a magazine or something on your kindle.
9) My laptop, because I will cry if it doesn't survive the trip, if I put it into my check-in bag.
10) My Phone and Earphones. I decided to put this in, because some people carry their phone and earphones in their bag. Either way, it's an essential, as I wouldn't survive not listening to music.
11) Electric devices accessories. Some plane have a on flight thingy ( I don't know the name... as you can tell), where you can charge your phone or plug in your laptop.
I hope this helpful for some of you and that it will help you pick lighter.
Have a safe journey ♥