Just as an example…
You can never be absolutely sure, but it’s a good bet that the guy in this picture has been on a few airliners in his lifetime…
He’s dressed for it. Long sleeves, long pants, natural fabrics, sneakers. The very best combination of comfort and safety (in the event of an evacuation). A couple of jackets/coats that double as blankets and pillows on the plane (although my personal style/opinion is that one all-purpose jacket is enough). Never forget that there is always a chance you’ll get stuck somewhere with bad weather and spartan conditions, with only what you’re wearing and carrying with you.
There’s a good chance he hasn’t checked any baggage. His assortment of items leads me to believe that he’s wearing, carrying, or has in his rollaboard everything that he’s traveling with. Never check bags unless you have to.
His rollaboard is a giveaway. This type of small, 2-wheeled carry-on bag with the telescoping handle is the bag that frequent travelers eventually buy after they’ve been through a couple of crap bags and a spinner.
He’s got something to do while he’s waiting in line, instead of just staring into space.
Now he needs to work on getting some more frequent flyer miles, so he can use the short line at airport security. 🙂
Everything is dependent upon your personal desires, practicality, and safety. I’m a comfort and safety guy. Comfort because I travel a lot (over 200 days per year), and safety because I’ve worked in air accident investigation. I’ve interviewed survivors and seen the bodies of non-survivors. The results of wearing synthetic fabrics and loose-fitting shoes on airplanes, in the event of an accident or evacuation, are not pretty and will be with you for the rest of your life.
I used to be concerned with efficiency, and I still am, to some extent. However, I’ve also finally accepted that nothing happens quickly at an airport, or at least you’re far better off if you just assume that. Rather than being ultra-efficient, my current philosophy is just to relax and give myself plenty of extra time. Even more so than seeing someone who is ultra-efficient at the security checkpoint, I notice the people who seem totally relaxed at the checkpoint. They know the drill. It doesn’t go any faster just because you want it to, and everyone, even the most frequent of frequent flyers, eventually ends up stuck in a line or waiting around at an airport. It’s like the old pilot’s adage: “Time to spare? Go by air.”
One trick I’ve been using in recent years is the “feeder airport” trick. This effectively eliminates any security checkpoint waiting… for everyone, not just for people with TSA precheck. The way it works is that you base out of a small feeder airport that has short flights to two or more major hubs. You do all the front-end stuff at the little airport and never see the land-side of a big airport. This also practically eliminates traffic congestion and crowds in general. If someone is driving me, we can always park mere steps from the terminal entrance (front row, as close as allowed) almost every time. This is how the security checkpoint at my primary U.S. mainland airport looks every single time I fly. There is almost literally never a line. I haven’t a clue why they have two TSA agents working at the ID check.
This pretty much eliminates nonstops for me, but I don’t even really care. I haven’t seen the outside of or a security checkpoint at a major airport in over a year, and I don’t have to deal with the traffic and congestion, both in the airport and on the big-city roads that lead to it.
EDIT: This is just one example of what an experienced traveler can look like. Various travelers look and act in various ways. There is no one right way and just because it’s not your way doesn’t mean that it’s wrong (or right). There are a few absolute dos and don’ts, and there are a few things that most experienced travelers have in common, but every traveler does it a bit differently than everyone else.
However, this is just one example… It’s not the only example. There is no need to make argumentative comments. They serve no purpose and don’t prove anything. If you have other examples of experienced travelers and methods that you use and/or that you think are good advice, then you should post those in an independent answer to the original question, not as a comment to another answer.