A wise person said the best way to deal with unhappiness is by doing the things you did when you were 10. I haven't tried it so can't say if it works but I think it would.
My own idea is to do what you are passionate about and pursue it as a career and try to make money from it, because with money comes happiness. I'm only messing; money definitely doesn't come with happiness. That's the least of things it comes with. It comes with success. Success can be a lot of things to a lot of people. To some it's love, to some it's fame, it can be anything, depending on who you are. My idea of success is turning my passions into professions and achieving feats in my fields of choice. My passions are film, literature, t.v and journalism so I took courses in each and now I'm trying to produce my first film and I am always on sites that sell scripts and screenwriter forums trying to find a script worth making while working on my own scripts, and I'm writing short stories, trying to come up with ideas for novels and constantly sending away ideas for t.v shows to every production company in the country and beyond, and I write news articles and send them to editors. I send poems to magazines and songs to publishers. I'm also trying to set up a business. I am always trying to increase the gears of my life. Sometimes they grind and sometimes they slide into place. If you're not driving forwards you're rolling backwards. Towards a cliff that drops down into an ocean of despair.
I also have a long list of hobbies, which are important to have, when your soul needs to be settled or enlivened. Also every 6 months or so go to bed for 3 or 4 days. Close the blinds, turn off the phone. Of course get up every now and then to use the bathroom or drink a beer but basically just shut off for 3 or 4 days and you will come out of that absolutely rejuvenated and so buoyant-spirited. In the future scientists will discover it and proscribe it, I'm telling you. Tell the truth, because dishonesty can cause guilt which may lead to unhappiness, and be kind because when we are mean it rebounds back and manifests in us at a later date, according to something I read somewhere anyway, and I believe it.
Passions, hobbies, don't let your hands be idle, try to accomplish great things and be yourself all the way. Friends are vitally important also. You'll go nowhere without them. And they can lift you out of the funk. I should say, if you feel like you don't have any passions in life, you do. Everyone does. Everyone. I don't know if they are things you can make careers out of but I hope they are. And if they're not, do them anyway. Failing my advice, try what that wise person said about doing what you did when you were 10. We are here for you. Best of luck!