This is actually bad advice. Advanced password cracking software employ a combination of dictionaries and common phrases. Using written phrases that could be sourced from public sources is bad practice. It actually takes very little time to go trough huge databases (often public domain text sources) when cracking hashes.
So do not use common phrases from public domain literature. Build yourself a good pass-phrase of un-related words like: “jake-fuss-sunrise-counsel-casanova” (this was generated with 1Password). These are easy to remember and easy to write, and are in fact much more secure than long passwords where words have a common sense relation to each-other.
Also, don’t bother to mangle words by replacing letters with characters or slang, or by doing common misspellings. These are among the first techniques tried in cracking a password.
I highly recommend you change your passwords using a password generator that uses the technique I described above. Don’t use a single password, use individual unique passwords for each account. Oh, and ore more thing, use a password manager like 1Password or KePass. Stay away from browser extensions that pretend to be password managers.