Keep a travel bag ready
I've decided to branch a list inspired by Nicola Fisher.
1. Be willing to pay more for a good travel bag
I normally buy inexpensive items knowing that they may lack features or durability. Travel bags are an exception. You do not want straps, wheels, fabric, etc. failing when you depend on it most.
2. Do not get bags with built in chargers
It adds weight and there are more travel restrictions on them all the time. Portable power supplies and batteries are a better choice.
3. Drab is better
Bags that look too military or "tactical" and bags that appear very expensive draw special attention from thieves and officials. None of this attention works in your favor.
4. Buy a little smaller than you think you need.
No matter how small or large your bag is, you will find a reason for it to be full.
5. Always have a carry-on
While I normally travel with ONLY a carry on, even if you are checking luggage, have a carry-on with the barest of essentials. Ideally, this carry on will be small enough to fit under the airline seat in front of you but if it is your only bag it may not be possible. The only time I ever violated this rule I was travelling with a large bulky duffel and didn't want the hassle of wrangling a 2nd bag. This was also the only time I've had an airline ever lose my luggage. Quite an adventure.
6. Think outdoorsy and/or tactical
While we want to avoid "the look" I referenced earlier, many outdoor companies really do offer bags and luggage that is far superior to most suitcases and carry ons offered by other retailers. Just avoid most bags advertised as "ultralight". They will always cost more and are usually much less durable.
7. Handles are always the weak point.
Double check the materials, stitching, and connectors. This has by far been the most common point of failure in my bags.
8. Inspect before you go.
I have a couple bags that have been faithful companions for more than 15 years. But even they are starting to show their age and are facing retirement. Even the toughest, best quality equipment wears out. Check all seams, straps, zippers, etc. before each trip.
9. Hard or soft?
There are advantages and disadvantages to both. Think hard and make up your own mind. And be open to experimentation. I've always used soft sided bags, even as briefcases, portfolios, laptop bags, etc. but have been tempted to try hard sided.
10. Ask other pros.
There are people who travel for a living. Flight crews, some military, sales, business, mariners, some journalists. All of these folks will have different requirements for what bags they carry and why. Did you know there are lines of luggage marketed specifically to flight crew?
11. If you wheel, check the geometry.
Due to my height, I've never found a wheeled bag that works for me using 2 wheels. Either the handles are too short or the bag is too unbalanced or ....... I either have to forego the wheeled option entirely, (why have weight that won't be used) or use the more common 4 wheeled models, which are usually too large for what I want.