Buy luggage that is easy to carry
The first rule for carry-on luggage is that it must be light, easy to transport, have multiple pockets and compartments, and be functional. It is no good having a bag the perfect size and totally indestructible if it takes up the total weight limit when empty and is impossible to lift into one of those overhead bins. This generally means that hard cases and leather are excluded simply on the basis of weight. My preference is for ballistic nylon Ė itís usually light, sturdy and tear resistant.
The second rule for carry-on luggage is that you must be prepared to carry it. Airports are large places and it can be a long way from the check-in desk to the plane. Unlike check-in luggage, carry-on means just that Ė you carry it on to the plane and have to lift it into the overhead locker. Make sure that the handles are comfortable to carry, that it has the types of shoulder straps you like or even that it has wheels that work.
The third rule is that the luggage must be strong enough not to fall apart. Zippers are the most common fasteners and must be strong enough to close when full and not burst easily. Carry-on bags come in a variety of sizes and shapes and finding the right one for you requires careful thought. Do beware: not all bags sold as carry-on are the official dimensions. Check the size for yourself. Its dimensions should not be more than 56cm x 45cm x 25cm per bag. The exact dimensions do vary with airlines and should be checked.
The rolling upright is one of my favourites. Some are soft-sided, some are moulded, some have extra handles, straps, clips
and pockets. They all have at least two wheels and they all have a telescoping handlebar that extends allowing you to pull
it like a not-quite-trained puppy. Do check weight before you buy though because some are more than 5-6kg before you start