Most airlines allow up to one carry-on item (a small suitcase, usually up to 9” x 14” x 22” or 22cm x 35cm x 56cm), one personal item (a small backpack or purse), and two checked bags (bigger suitcases which will go in the cargo hold and you will not have access to until you arrive). Check with your airline on what sizes and weights are allowed. Most airlines will charge for the checked bags, and some will charge for the carry-on or personal item.

It is best to put anything you will need during the flight (snacks, laptop, medicine, etc) in your personal item. You will not be able to access your checked bags from shortly after you get to the airport until after you get to your destination.

Make sure you aren’t packing anything that’s prohibited. In the US, you can’t put Lithium-Ion Batteries into checked luggage, but you can carry them on. Don’t fly with illegal drugs. Especially internationally. Don’t carry on any fluids over 100ml or 3.4 fl oz. If you have to bring liquids, put them in bottles under 100 ml, in 1 bag that’s no bigger than 1 quart. Please don’t try to carry a knife onto the plane.

You can bring an empty water bottle through security, and you will have to fill it up after you get through the security checkpoint.

If you have any questions about where to put something, the TSA has a handy, searchable guide to what can and can’t be in the cabin or checked in.

If you are bringing both a carry-on and a personal item, make sure you can lift the carry-on above your head. We’ll come back to why you need this one once you’re getting on the plane.

For longer flights, you might want to bring a pair of wired headphones, in case the airplane has an in-flight entertainment system (more on that later). Some airplanes are starting to allow Bluetooth headsets, but those are few and far between at the moment.

You might want to put a light jacket in your carry-on bag. Airports and airplanes can sometimes get cold, even in the summer.

Try to leave yourself enough time to pack before you have to leave to the airport. Hopefully, you’re mostly packed by the day before your flight.