How to solder correctly, and what are the problems and difficulties?

Question

Electronics

Guys, I also had experience with a soldering iron and soldering. Observing the polarity, I decided to solder a toy for myself.
Of which 1 switch for 3 legs, 2 modules and a battery (casting)
What didn’t work out for me was that when charging the battery through the USB port in the module, the battery began to heat up slightly, the battery began to swell a little, and the switch Stopped responding and now it doesn't work at all.
Below there are photographs of the soldering and what is stuck where, I am not a master at drawing schemes, so I photographed it.
I want to note that both in module 1 and in the second there are connectors for charging, they differ only in micro USB ports. 2 modules are a mini player with a sd card and a volume and track switch, and the second is a bluetooth module (it has absolutely nothing to do with the player, if you think that I'm somehow trying to output audio via bluetooth) and so, the second is a bluetooth module, makes the photo or sound higher when connected with any phone. And now I don’t know how to properly solder me, so that nothing burns and works fine. Thank you))
If possible, explain without strong use of specific terms.

spoiler

Answer 1

You hooked the switch parallel to the battery, but you should have cut it.
You pulled the switch in 1 of the positions, which shorted the battery. Battery life is questionable. Switch - too, he did not count on such a current at all.
You had to connect from so. In the left position of the switch - battery charging, in the right position - load operation, what do you have there ...

And if it was necessary that from one switch both the charging and the load were turned off at once, then like this