Some rule of thumb creating password for your computer and or online account:
-Do not contain your username. Example your username is james.bond, your password should not contain that word, eg. jamesS3cre7.
-Do not contain any of your personal information, eg. your real name, place and or date of birth, your pet's name, your parent's name, etc. Its social engineering, easy to identify your self by people or things around you.
-Easy to remember but hard to be guessed. Your password should contain lowercase, uppercase, number and special character eg. !@#$%^. Example, Gl0b4lwaRminx.
-Change your password at least every three month.
-You should not use same password for your critical service account such as your Internet Banking, with other service such social network sites.