Happiness happens in the core of our emotions. It is a surface wave on the surface of our mind. Creating happiness means creating a powerful emotional foundation in the core of our being.
The best emotional foundation you can have has to do with your cosmic identity. Your personal identity is great, very valuable and has the potential to give you lots of satisfaction. This is your job, career, family, worldly activities etc. Don't give up any of that. Instead simply ad something more.
Bring your very cosmic or spiritual essence in the core of your being. How? techniques like hatha yoga, meditation, raja, kriyas as well as other techniques from other spiritual traditions have the same goal: bringing a universal dimension in the core of our lives.
Here is your first technique
Use Sanskrit calligraphy:
Shiva - Shakti
They are personified deities but they are as well cosmic or universal principles. By writing these words down you are inviting your cosmic identity in the core of your being.
Whenever you feel an emotional gap, lack of happiness, write these words down on a white paper. Repeat it as much as you want, daily, whenever you feel like, wherever you are. Write it down and keep what you wrote. Keep it around, in your house, in your pocked, wallet, etc.
You can as well whisper, remember, focus on the mantra, repeat it internally when meditating or when laying down to sleep in the evening.
To integrate a technique, you should try it for a week or so (a lifetime if you feel like...). After that the technique becomes a habit pattern you can tap into whenever you feel like.
How does it impact in you?