Family + Commandments + Scriptures + Temples + Work + Priesthood = Happiness
How do I know this? And where is the proof? Take a look in the Book of Mormon, 2 Nephi 5:
1. Family. Nephi's older brothers don't really like him. In fact, they want to kill him. So what does Nephi do? He "flees into the wilderness" (verse 5) and the first thing he says he takes with him is his family (see v. 6).
2. Keep the Commandments. Nephi tells of the first thing his family does as they settle in the wilderness: "...we did observe to keep the judgements, and the statutes, and the commandments of the Lord in all things..." (v. 10)
3. Study the Scriptures. Another thing Nephi mentions bringing as he fled into the wilderness were the "plates of brass" (v. 12), or their current scriptures. Nephi and his family read and prayed about this record often.
4. Temple Attendance. Once Nephi and his family settled down what was the first thing he speaks of building? Temples! "...after the manner of the temple of Solomon..." (v. 16) they built and worshiped in temples.
5. Work. Work fixes that which doesn't work anymore. Nephi taught his people that they needed to "labor with their hands" (v. 17) or to learn to work for themselves. A valuable trait we all need to learn.
6. Priesthood and Following the Prophet. The last thing Nephi mentions doing is ordaining his younger brothers to "be priests and teachers" (v. 26) so that the people would have the blessings of the priesthood to lead and direct them.
So how does this equal happiness? After describing the pattern that Nephi and his people live, he tells us of their standard of living. He says "And it came to pass that we lived after the manner of happiness." (v. 27) If we follow this pattern, set by a prophet of God, we too will find that we are living "after the manner of happiness." Now go be happy!