If you find yourself making a male-to-male adapter stop. Question all the steps that lead you there. Probably find another way.

Check that the electrical power is off with a meter. Don't trust that you shut the switch. Some really creative wiring or frayed wires can cause them to be unexpectedly live.

If you're cleaning, don't mix bleach and vinegar. It produces chlorine gas which can kill you.

Learn CPR for infants and small kids. It's usually a different or additional class to standard adult and kid CPR that I think goes down to 2 year olds. You don't want that memory.

Always wait a second before going if you're in the front after light turns green. See too many fucking murderous psychos trying to save 20 seconds by roaring through fully red lights that they missed when it turned from yellow.

Add a water filter with pump to your survival kit. Costs like $20 bucks and means you could drink out of a damn stream in a disaster if mains burst, etc. given the state of poor emergency response and planning that has been on display in the US since Katrina and continues through COVID, NO ONE is planning or going to save you. Water is as important as it gets.

Insulated foil bags/blankets for your car. If you get suck and have to sleep overnight, if you run out of gas they might mean the difference between keeping toes, legs, fingers or your life. They're like $5 and smaller than a deck of cards and weigh almost nighting.

Always have a hatchet in your trunk. It's a hammer, a cutting tool, weapon, and 500 other things I learned reading The Hatchet as a kid.

Know how to find north, and read a map.

Go for your free annual checkups, especially if you're healthy--keep yourself that way!

If you party around people who do hard drugs (festivals, shows, etc), get a narcan inhaler and know how to administer it. It's very simple, and there are orgs that will give you one for free. Fent is way too common, and there's other bad shit out there. You could save a life.

Use jack stands for your car. If your body will be under the car for even a second, there should be jack stands. There were five different people at my high school who were in a wheel chair because they thought the jack was enough.

I don't care if your jack costs $100,000 made of pure titanium; do not trust it.

Don't carry a gun unless you put the work into the learning curve. And it's a steep curve.

Make safety an unbreakable habit, and that takes practice. Shoot with someone more experienced, let them correct your mistakes, no matter how minor.

Putting steel on target, especially under stress, takes mad practice. If you haven't put 1,000 rounds through your personal weapon, leave it at home. How do you trust a gun you haven't shot 1,000 times?! Hell, 200 rounds is standard "break in" on a new pistol.

Can you draw it and get on target, shaking yourself shitless? Because if that day comes, you'll be scared shitless. Have you tried? Try. Run until you can't breathe, draw and fire. Try. Now do it again.

You don't have to go nuts memorizing ballistics charts, but have an idea what you can expect from $round at $range. You're going to have to watch a fuck-ton of videos, and practice, to get a real-world idea of what you're carrying and what you can do with it. Adjust accordingly.

Most people are woefully ignorant of what their state law allows in self-defense. Seen the craziest comments from such people. Hint: The law allows far less than you probably think, even in the reddest of states. Again, fuck ton of videos. Learn, or you might find yourself in a concrete and steel cage.

One more thought; A pistol is not a magical self-defense talisman. A gun is not a, "Get off me!" or "Leave me alone!", ward. A concealed gun is for one thing only, killing the person you show it to. If you cannot do that thing, I get you, and I'm with you, but don't carry.

Much the same goes for a home defense gun. Learn and train. Or do not. You're my friend either way.

(I'll plug Paul Harrell's channel. Zero politics, just the facts, stated and demonstrated, mildly amusing. Hundreds of videos on gun related subjects. And some fun presentations outside the gun world!)

• Never ever stand next to a loaded chain or a rope when something is being towed or dragged. - If, and eventually when, that thing snaps it will cut you clean in half or cause a very painful injury;
• When messing with wires that might be powered never use both of your hands. - If you get shocked you reduce chances of serious injury significantly;
• Never wear gloves and too long sleeves when working with rotary tools. - If a tool catches your apparel it will pull the rest of the hand into it;
• Don't enter steel containers that only have top hatch (like boat anchor chambers and similar). - Process of rusting is consuming oxygen. Entering such room which has no ventilation is deadly. There's no time to even notice something is wrong and you'll just pass out and die;
• Avoid painted parts on the road when riding anything on two wheels. - During the summer this is not a problem, but making a habit is a useful thing. The very first rain or frost will make painted parts be as slippery as ice;
• Always assume everyone in traffic will kill you. - There are no safe assumptions. If a person has turn signal on, only certainty there is that they have turn signal on. Don't assume they are turning. Wait for them to start their action, then react. This is especially important if you are cycling or riding a motorcycle;
• Always obey the traffic rules, even if there's no one close by. - Rules are set in place to make everyone behave in predictable manner. The fact you didn't see anyone doesn't mean there's no one around and doing something unpredictably can kill you. One stupid example is when someone lets you merge but they have right of way. Doing such a thing makes it a very dangerous situation to everyone else who have no idea what to expect.

Before getting on a ladder double-check that the feet are placed firmly and (for extension ladders) the angle is not too steep.

Cutting down trees of any real size is incredibly dangerous. They can kick or barber chair and instantly kill you.

If you need to put out a small kitchen fire in an emergency and have no other way to do it rip the top off a box of baking soda and use the contents to smother the fire. As the baking soda heats it releases CO2 starving the fire of oxygen, the remaining salt also prevents oxygen from reaching the burning material.

Even better, always have a fire extinguisher handy in the kitchen - don't bury it under the sink or in a closet.

Always cut away from yourself (and others).

Never ever EVER walk under a forklifts raised load (the pallet it's carrying).

Things can fall from it, the hydraulics can giveway, the operator may not see you and lower it on you.

Especially an 'order picker' as the operator can not see under them.

Never go in against a Sicilian when death is on the line.

Loosen (but do not remove) lug nuts from a wheel, before jacking up the car.

House or apartment, make sure carbon monoxide detectors are installed NEAR GROUND LEVEL.

So many slumlords do not even give a fuck, and many homeowners think they are just some other kind of smoke detector.

EDIT: bus_factor has pointed out to me that this is actually a common misperception. CO actually more or less evenly dissipates in a room and does not settle near the floor.

https://pubmed.ncbi.nlm.nih.gov/21536403/

Im now going to think about my life choices that lead me to this moment, and more importantly:

Go out for a breath of fresh air =P

If you have to secure something heavy to work under/beside it, secure some more.

My dad nearly lost a hand to it.

Springs again, do not replace car shocks with a cheap spring compressor, my cheap ones bend and slipped when the springs were fully compressed. Literally like a mini explosion

Computer Power Supplies (PSU)

Unless you have very specific training on opening one up, discharging it properly, and the skills to repair it safely for future use, just buy a new one when yours dies.

This is certainly a case of the phrase "voltage hurts, amps kill" to the best of my knowledge.

I received the above advice and heeded it.

My second IT job was filling the role of someone who never received this advice.

I replaced the spring on a garage door.

It's officially the most dangerous thing I've done. Even if the door hadn't almost crushed me it would still rank way up there.

I've worked on the Water with little LEO presence. I've carried a rifle for my queen. I've taken the crowchild to Glenmore exit in full drift in winter. I've fallen on my head, been run over, almost lost my arm, separate incidents. Swapping the spring on the garage door - in a rental no less - is still the riskiest and dumbest thing I've done.

So far.

Replacing torsion style garage door springs can be dangerous, but replacing extension springs is fairly straightforward and safe to do yourself. Extension springs are the ones that are parallel to the tracks the door slides on and should not be under any tension when the door is open.

One downside to extension springs is if/when they eventually break it’s likely to happen when the spring is under tension, and pieces can fly around the garage. To prevent this, string a length of wire cable through the center of the spring and attach it to the wall/ceiling at either end when the spring is extended. Leave a little slack in it so that it doesn’t interfere with regular operation of the door. This will prevent the pieces of the spring from shooting around the garage if it does break under tension.