Password security short, medium, high levels

Hello Information Security,
I would like to make a question that could be possible used in the future for a reference regarding
the way someone can protect his passwords as much as possible.

Firstly, what are the steps that someone has to do if he has only basic computer skills (common Windows / MAC user?)
for good, high, and if it is possible insane security? Could this be used on a large scale by most computer users if they are trained properly? (would even matter?)

Secondly, what are the steps for someone who has basic programming skills and he would like to try things to an extend (as long as are not more than difficult to maintain and compromise himself due to lack of skills/experience). Again for good, high and insane security.

Lastly would be for those who know what they are doing regarding security and have been working in large companies? but probably they don’t even need this guide.

Thank you for your time!