Elements of a Strong Password

Length Matters: The longer your password, the harder it is to crack. Use a minimum of eight (8) characters.
Mix it Up: Include upper and lowercase letters, punctuation, and numbers. Select a letter to capitalize at random; try to avoid the first letter.
Avoid Dictionary Words or Proper Names: These are easy to guess. If you are going to spell out a word or phrase, remove letters, replace them with numbers, or deliberately misspell the word or phrase. For example, "I Hate Peas" can become "eyeH8pEEz".
Avoid Personal Information: This includes birthdates, names of family members or pets, and address information. Try an acronym instead. Example: "You can't teach an old dog new tricks" becomes "yctaodnt".

It is strongly recommended that passwords:

Contain 10 or more characters
Use all 4 of the character sets listed above
Do not contain Full Name, Given Name, Surname
Do not contain personal identifying information (e.g., last name, SSN, date of birth)
Avoid a capital letter as the first character (e.g., P2meetY0u)
Avoid a digit as the last character (e.g., p2meetyo9)

How to Choose a Secure Password:

There are plenty of ways to come up with passwords that meet the criteria above.

Method 1: Use the first character of each word in a phrase, song or poem to create a "mnemonic". For instance:

Start with "If you can't beat a computer at chess, try kickboxing".
Take the first letter of each word: "iycbacactkb".
Vary it with special characters, punctuation and capitals, and you've got "Iycbac@c,tKB".

It looks like 12 characters of gobbledy-gook, but it's (1) long enough, (2) complex enough, (3) easy enough to remember - so it's a good password.

Method 2: Alternate between one consonant and one or two vowels. This provides nonsense words that are usually pronounceable, and thus easily remembered. Examples: routboofip or quadpopgoor. Then exchange some letters for numbers, and capitalize some of the letters: routb00fIP QU@dp0pgooR

Method 3: Choose three short words and paste them together with a punctuation and numbers between them. For example:Dog;rain2sit book+Mug=sleep kid5.goaT!fish