Just live life to the fullest. follow God and his commandments and everything will be fine. Put your trust and faith to him and he'll take care of the rest.
nothing ever stays the same. everything is always changing. i can not tell you how to be happy forever because its honestly impossible but i can tell you that in my case, something bad is always happening so its impossible to stay happy. the love of my life is locked up, and ive had a past of rap.e, abuse, abandonment, and severe heartbreak, and drug addiction and gang affiliation. Happiness is always coming and going.