How to create a truely secure password which is easy to remember

As you probably already have seen, there are a million tips for how to create a secure password. 99,9% of them are quite useless because they end in some complicated stringchar-mixups.

What is the most important factor in pw security? LENGTH! (espsecially in regards to BruteForce)

"Hello.........................."  is more secure as  "skfjdf3AKJD/("  - Because its longer!

So a secure password does not have to be some complicated stringchar-mix.

My Recipe: 

Use sentences! Why? Because they are long, they have UPPER- and LOWERCASE and most of them end in a symbol or they contain other symbols. Length should not be under 12 chars!

Example: "IloveDouglasAdamsbecausehe'sfuckingawesome" <-- easy to remember and extremely strong because its 42 chars long!
Cracking that by Brute Force with a 100 Trillion guesses/sec would take:

3.49 billion quadruple trillion centuries (Calculation by https://www.grc.com/haystack.htm )

Other Examples:

• "MyfavouritebookistheC-ReferencebyDennisRitchie"
• "DreamTheaterandSymphonyXandPinkFloydrockhard!"
• "Iamtoolazytofindanothercreativepasswordexample" <-- no one would guess that :D
• "Somewhereovertherainbowbluebirdsfly"
• "BarneyfromHowIMetYourMotherisAWESOME!"

XKCD approves:

source: http://xkcd.com/936/