Keep your pockets closed
This is not a post about security. This is a post about the simple things based on experience that are passed along to you and that stay with you, making your life smoother and tackling all what's coming, especially when you are under stress or your life depends on you keeping your head.
When I was in basic training SSGT M, our drill sergeant, made sure we would always button or zip our pockets or rucksacks closed. He was very serious about it. He would make our lives miserable if he'd find one of us with a trouser pocket unbuttoned or one of the rucksacks compartments unzipped. We would run forever, go down for pushups until our hands bleed, or skip meals. There was no way we would forget to button that pocket flap, even after having spend a 72 hour brutal evolution, when your mind is completely empty and you can't think anymore. Those pockets will remain closed. We would make sure of that.
At that time I didn't understand why he was so maniacal about this.
When we finished boot camp and moved to advanced training, he moved with us and became our platoon Sergeant. We could talk to him then and so we asked him the reason behind his obsession with the pockets. He replied:
When you are in combat, running, jumping, shooting back, trying to keep your men alive... You don't want to start wandering. You have a mission, and under stress that mission is hard accomplish. I'm giving you the discipline to see this through. If you can't keep your pockets closed, something so simple, how can I expect you to lead men in combat, to see the mission to the end? When shit hits the fan, and it will, how can you have the wits and clarity of mind to fall back to your training? Discipline. Discipline. And, well, you don't want to find out when you life depends on it that your SERE kit or med kit are gone because you left that trouser's pocket open? Right? By forcing you to close those pockets and making it second nature to you, you will always have your gear with you. Now translate this to everything else you do: mission planning, gear prep, comms, etc... Discipline. When you force yourself to do something, even if you don't see the immediate benefits, it will allow you to be free.
That was 20 years ago. Even today I close all my pockets automatically. It stayed with me. It saved me in more than one occasion when in combat or climbing. By closing those pockets I learned discipline.
The same applies to other things. Pay attention to details, get your gear ready and practice, practice, practice. Make the use of each piece of gear second nature, learn each piece of gear, each of its features and how to use them as if your life depended on it, it might one day. Choose the simplest and most reliable gear, even if it's a bit more expensive. Under stress, when you really it need, it won't let you down.
Keep your pockets closed.