WANT TO KEEP CALM and carry on? Start with first-class rolling luggage. A 22-inch trolley, which can be stowed overhead on most domestic and international flights, is what you need. Next, four wheels (preferably multidirectional) are better than two, as are several handle options, including the top, the side and a sturdy telescopic handle for pushing and pulling. A suitcase with “sandwich” construction (meaning two halves) makes organizing easier, as do internal and external pockets. If you can pack all of that thinking into one bag, there ought to be enough room for a two-day business trip. And now you’re ready to roll.