Minimalism: the art of packing light

I (Jen) love being a light packer. It took me years of moving in and out of apartments & hotels, too many flights of stairs and a few transportation mishaps to learn one simple truth: having a lot of baggage holds you back. It wasn't easy to cut out the fat. Consolidation requires some thought and soul searching to see what you really need when you go out and face the world. There's the good side and the bad: in a hotel with no elevator, you'll find me at the top of the stairs trying not to look too smug as my friends struggle to ascend with their wheeled luggage. But if I overdo it and under-pack I am the grungiest one in our group photos and when things get desperate, I even start to fantasize about laundry machines. It's a work in progress: packing exactly what you need (nothing more or less) truly is an art, and the journey starts with a fantastic carry-on.
Your luggage defines your parameters- the temptation in using an oversized suitcase is, of course, filling it with unnecessary crap. Get a small bag with handles and shoulder strap that can fit under your seat if necessary. It'll serve you well in other countries: European and Asian budget airlines such as EasyJet and AirAsia are really strict about their carry-on policy. To summarize:

USA: 1 carry-on (60x40x25cm) + 1 personal item
EasyJet (EU): 1 carry-on (56x45x25cm)
AirAsia (SEA): 1 carry-on (56x36x23cm) + 1 personal item

I've seen too many people have to repack or pay extra fees at the boarding gate for oversized luggage, so I like to make sure I have a bag that works across the board. It's also worth it to spend a little more on well-designed luggage because tensile strength is a real thing, and I'd hate for one of my straps to break in the middle of crossing a busy street. Go with a bag that's great looking as you will be using it often, but I'd stay away from the ones with designer logos all over them- they scream "ROB ME!" in airports.

Having a fantastic bag is half the battle- I currently use and love:
Weekend bag by Orla Kiely (38x44x23cm) - trips up to 5 days.
MEI Voyageur (55x35x22cm)- backpacking and longer trips