It should contain at least eight characters
It should contain a mix of four different types of characters – upper case letters, lower case letters, numbers, and special characters such as !@#$%^&*,;” If there is only one letter or special character, it should not be either the first or last character in the password.
It should not be a name, a slang word, or any word in the dictionary. It should not include any part of your name or your e-mail address.
Following that advice, of course, means you’ll create a password that will be impossible, unless you try a trick: Turn a sentence into a password.
For example, “Now I lay me down to sleep” might become nilmDOWN2s, a 10-character password that won’t be found in any dictionary.