I'm a bit confused here. If you are advising "non electronic people" how to join two wires, shouldn't the goal be to offer up the best ways to accomplish that. Note the plural "ways" as there is no one best way.
So I'd have to think that you need to address proper soldering of wires, it doesn't matter if their skills suck or they don't have the proper tools. Frankly at this level they probably don't have any tools too do any approach properly. Beyond that when I first was exposed to soldering wires I didn't have any soldering tools at all, so I don't see an argument here.
Second; it is pretty hard to dismiss other common methods used widely. These would be crimped connectors and wire nuts (residential wiring). Both of these are equally hazardous if not used properly. Crimped connections are more common in electronics and these need the proper tools to be used effectively so you are back to the issue of tools.
The third issue is related to protection of those joints, which in many cases means shrink tubing. The thing here is that again there are many choices when it comes to shrink tubing requiring an explanation of the types and their features. Many people don't even realize that there is the concept of the melt liner tubing (tubing with glue inside as many call it) that offers a different seal compared to single layer shrink tube. Then you have rigid vs flexible.
At the very least you need to address soldering and crimped connectors and leave open the idea that this is not all there is. At the same time you need to cover protection of those joints. The trick is finding the right level of detail to introduce people with zero background. I just don't see where not having the right tools is an issue because you have to be willing to invest in those tools to actually do such work anyways.
Consider something similar like courses that teach non mechanics to do maintenance on their cars. Some of those tasks require tools, sometimes very specific tools, the person taking the class either needs to be willing to buy such tools or they will make a decision that it isn't worth it. The same thing is going to happen when introducing people to methods to splice wires. Either the purchase of tools is worth it to them or not. Since almost any method requires tools, soldering of wires should not be dismissed on that issue alone.
I had to advise non electronic people how to correctly assemble two wires together.
Now these persons do not have a decent soldering iron or decent solder experience so soldering the wires together was not really an option.
The Wago 221 clamps are so so mechanically decoupled, rather not they are only electrically clamped, also not an option. Then I advised the 3M low voltage gel connectors or the crimp connectors iften used in cars.
Someone recommended these low temperature solder shrink connectors.
You strip the wires overlap the stripped area in the middle where some ring of low temperature solder is positioned. Then use a paintheatgun to solder and shrink the connection.
I have no experience with these.
My first thought was, not sure if the electrical connection is good enough.
Does anyone of you have experience with these and what are your thoughts ?
On a side note, I know that there are many homes in the USA that don't have any tools at all. This sort of shocks me growing up with a garage full of tools that my father owned. He however had very little that would be consider electronic or electrical tools so even with this exposure growing up I still had to learn about the proper tools for the various jobs in the electronics / electrical world.
So don't be surprised if your task to teach about wire splicing needs to be reduced to explaining the function of the simplest of tools. That might even require explaining the difference between screw drivers, or what a wire stripper is.
I forgot to mention one thing. I don't use those shrink connectors with the built in solder for a couple of reasons. One is the process of inspection, which in my opinion needs to be done in each step of the process. In a solder joint that is mechanical and visual inspection of the joint which isn't possible with these connectors. Yes I know that the sleeves are supposedly transparent. However with any connector I want to visual inspect and mechanically inspect (give it a tug) to make sure there are no gross failures. With most connections this is easily done before you apply any sort of insulation / protection. Even if the low temperature solder shrink connectors worked properly, you really can't do either of these to my satisfaction. This is one reason why I often prefer non insulated crimp connectors.