Say and do what you mean, but never say and do it meanly.
Happiness can be thought, taught and caught... but not bought.
Anyone too busy to say thank you will get fewer and fewer chances to say it.
If you find yourself plagued by a recurrent worry, train yourself to think of something else. Your conscious mind can concentrate on only one thought at a time, and driving the negativity away will free you up to move forward again.
Believe in yourself, even when no one else does.
Good habits are as addictive as bad habits, and a lot more rewarding.