I like these infographics, even if they are a bit simplistic, they’re upbeat.
By H34DUP and David Meiklejohn. Source: blog.h34dup.com
A quibble: humans adapt to positive emotions quite readily, as Phillip Zimbardo and John Boyd wrote in The Time Paradox. So the advice “Keep doing what you’re doing” would probably maintain happiness, but only for so long. Humans also need novelty, variation, and new challenges.
Plus, for you-know-whats and giggles (unless you’re an information graphics designer for which chartjunk is a curse upon the earth of Biblical proportions):
The usually illustrious Christoph Nieman’s illustration for Portfolio.com: