Here is a simple yet effective technique I have tried and it works everytime. Not going to give a philosophical lecture that why it works, the simple thing is that we are programmed to seek happiness, comfort, and pleasure. And you can use hack your social life using this loophole.
Act happy. That's all it, act happy like you have won a lottery ticket, like the world is completely fair and free from suffering, like you are going to heaven after you die...
I am not telling you to be happy, that might be not even possible for you. You might have a stressful job, you might have a cynical and logical mind, you might notice the unfairness of the world more than others, you might be treated by others like shit, you might not have basic human needs and relations to live a happy life.
The key is to pretend. Just try it, and see the results. Talk positively about everything, every fucking thing, even if it makes you cry from inside. Mother died? Feel any emotion you want to feel but show to others that you are thankful, she must be in suffering and death have freed her of it. Hamster to the next level. Show others that you can't think negative.(Death of mother is just to illustrate an example, hopefully you won't start arguing about it)
I am myself nihilistic, cynical, and always complaining guy. I pretended to be happy, and oh boy the attitude of people towards you shift significantly. Everyone's a sucker of happiness, and when they see a happy person they want to get associated with that person. Because they think that they can get happiness out of you. That person must have something already that they are seeking, something that if they will get they will finally become happy.
Works with the chicks too. Chicks nowadays have a abundance of choice, with one swipe they can bring a guy that can distract her from feeling like shit. They now have low tolerance for the guy who is not making giving her mental high. The guy who isn't happy can't give her any kind of high. She rejects you. I shamelessly tell girls, that how much awesome and happy I am. And they easily believes me. The truth is that I am depressed from inside, and later if I even tell them that the awesome me is just a lie, they would shut me up. Not because they believe me that I am actually awesome, its because they themselves want to keep believing that I am awesome so they can continue associating themselves with me.
Debating that such thing is right or wrong is an interesting topic. But here I am only sharing a trick with you, its upto you to experiment with it or not. I only knows from my experience that this trick is 100% effective.
One advantage of pretending to be happy over being actually happy is that by pretending you are not dependant on the external world. Shit happens all the time, but it won't be effecting your simulacra since its not real at the first place. If you rely on actual happiness, then you will break the moment the shit happens and a negative thought appears in your mind.
Also you will learn to be not anxious. You will be allowing negative thoughts to appear without getting anxious about it, since you won't be putting pressure on yourself to be happy all the time.
Deception makes you powerful. Learn this art.
Edit: It is not at all a guide to be happy. It is a guide to increase social value, or become more likable and fuckable. If it helps you actually become happy, then good for you.
Edit: Or you can just play this song in your head https://www.youtube.com/watch?v=JoQ4GidQP-k