Drop it off a cliff, hit it with a hammer, jam a incompatible component in the wrong slot, jam a incompatible component in the wrong slot with a hammer, etc. Not what I mean.
I am asking about commonly overlooked things to do to protect your computer when upgrading. Do I need to upgrade the BIOS? Create a backup of the hard drive/prior drivers? Uninstall something? Make sure that my laptop battery is removed and that you give some time for it to "let the power drain out"? Discharge capacitors... you get the point.
So what are all the precautions when I am changing some basic components? (RAM, WiFi, and adding Bluetooth (if there is a slot)?
Edit: Forgot to say that one other thing that would be useful is a resource that can tell if a certain part will fit physically in your computer, if that would be a problem on a laptop. Sorry, I left that out.