Three short chapters after Lehi declared that "men are that they might have joy", Nephi reports that his people, now distanced from his dangerous, short-tempered brothers, lived "after the manner of happiness" (2 Nephi 5:27).
At first glance, Nephi's life may not look particularly happy. His father and mother had passed away, he lived in the wilderness where hard work was required to survive from year to year and he made swords in his spare time to defend his family from his brothers who would attack from time to time.
Obviously, those aren't likely the details to which Nephi referred. Instead, consider this list of behaviors that he mentions in that same chapter. As you read, contemplate which of these you are doing, which you could do better and how your life could be happier. Nephi reports:
We did observe to keep the judgments, and the statutes, and the commandments of the Lord in all things (v. 10).
The Lord was with us; and we did prosper exceedingly; for we did sow seed, and we did reap again in abundance. And we began to raise flocks, and herds, and animals of every kind (v. 11).
I, Nephi, had also brought the records which were engraven upon the plates of brass; and also the ball, or compass, which was prepared for my father by the hand of the Lord (v. 12).
We began to prosper exceedingly, and to multiply in the land (v. 13).
I, Nephi, did take the sword of Laban, and after the manner of it did make many swords, lest by any means the people who were now called Lamanites should come upon us and destroy us (v. 14).
I, Nephi, did build a temple (v. 16).
I, Nephi, did cause my people to be industrious, and to labor with their hands (v. 17).
I, Nephi, was desirous that [my people] should have no king; nevertheless, I did for them according to that which was in my power (v. 18).
By doing these things, Nephi writes that his people found happiness. The same principles can be likened to us today. As we live the gospel, we can be happy despite whatever else may be going on in our lives.