There is a lot of advice floating around dealing with what to do with passwords. Companies choose policies which are against expert advice, sites use poor policies forcing users to create insecure passwords, and websites fail to notify users when data breaches have occurred.
Please take some time to read advice from security experts and protect yourself properly. There are many places you can find great advice, below are just a few.
Steve Gibson's Resume
Password Haystacks is a way to easily remember, yet strong password concept.
Security Now Episode 303 talks about Password Haystacks in depth. Episode 303 Transcript
Security Now Episode 256 talks about LastPass and why you should use it. Episode 256 Transcript