Here is a collection of ideas relate to happiness.

Do What You Love

You've got to find what you love. And that is as true for your work as it is for your lovers. Your work is going to fill a large part of your life, and the only way to be truly satisfied is to do what you believe is great work.

And the only way to do great work is to love what you do. If you haven't found it yet, keep looking. Don't settle. As with all matters of the heart, you'll know when you find it. And, like any great relationship, it just gets better and better as the years roll on. So keep looking until you find it. Don't settle.¹

To be happy I think you have to be doing something you not only enjoy, but admire.²

Flow

The positive aspects of human experience - joy, creativity, the process of total involvement with life I call flow.³ p2

The best moments usually occur when a person's body or mind is stretched to its limits in a voluntary effort to accomplish something difficult and worthwhile. Optimal experience is thus something that we make happen. ³ p3

Attachment

What is an Attachment? An emotional state of clinging caused by the (false) belief that without some particular thing or some person you cannot be happy.⁴

The root of suffering is attachment. - Buddha

Freedom and Peace of Mind

Freedom is freedom from the mind. The only reason that any human being is not free is because of his mind. It is the mind which creates his tortures. It is the mind which creates his anxiety. It is the mind which creates his conflicts. It is the mind which creates his rules. All that he is confined by, all that he is imprisoned by, is the mind. Not anything else.⁵⁶

Buddhism - Suffering

Suffering is an inherent part of human existence. This suffering includes not only physical pain but also emotional distress, dissatisfaction, and the impermanence of all things.
The cause of suffering is are attachment, craving, and clinging. This attachment leads to desires, expectations, and a sense of self that can result in suffering when these desires are unmet
Suffering can be transcended and overcome by letting go of attachments and desires. This cessation of suffering is attainable through spirtual practice and transformation of the mind.
Practices. Buddhism offers a holistic perspective on suffering and provides practical tools for addressing it:
- Mindfulness and Meditation: Mindfulness practices and meditation techniques are central to Buddhist philosophy. They help individuals become aware of their thoughts, emotions, and sensations, allowing them to develop a deeper understanding of the causes of suffering and how to respond to it.
- Non-Attachment: Buddhism teaches non-attachment as a way to reduce suffering. By letting go of attachment to desires, outcomes, and the impermanent nature of things, individuals can experience greater equanimity and freedom.
- Compassion and Loving-Kindness: Cultivating compassion for oneself and others is a core aspect of Buddhist practice. Compassion helps individuals connect with the shared human experience of suffering and develop empathy for others.
- Impermanence: Buddhism emphasizes the impermanent nature of all things. By understanding that everything is in a state of constant change, individuals can develop a more open and accepting attitude toward life's challenges.

Again and again I therefore admonish my students in Europe and in America: "Don't aim at success - the more you aim at it and make it a target, the more you are going to miss it. For success, like happiness, cannot be pursued; it must ensue, and it only does so as the unintended side-effect of one's dedication to a cause greater than oneself or as the by-product of one's surrender to a person other than oneself. Happiness must happen, and the same holds for success: you have to let it happen by not caring about it. I want you to listen to what your conscience commands you to do and go on to carry it out to the best of your knowledge. Then you will live to see that in the long run - in the long run, I say! - success will follow you precisely because you had forgotten to think of it." ⁷ XIV

"Motivation"

There are a lot of aspect of happiness comeing from no-attachment, no desire, then there is a question "How do I motivate myself?". For majority of the "normal" people, it needs time to practice to achieve those state. There are indeed "solutions" for the motivation,

Select very few "meaningful" goal (or desire): reduce attachments
Work on what you love and find interesting things to work on: follow the nature of self, be self
Cultivate interests in solving important problems⁸: it might take time to find what one is really passionate about, life is full of problems⁹, so enjoy solving problems, but not all problems are equal, the important problems can create values for other and oneself.
Practice as Buddhism suggests above:
- Mindfulness and meditation.
- Compassion and Loving-Kindness: for oneself, others, and humanity.
- Acknowledge the impermanent nature of all things, embrace changes and new.

Happiness