This is a succint and concise summary of the noble eightfold path as I currently understand it (-:
Birth, ageing, and death is hard to bear. Loss and separation from what we love is also hard to bear. Associating with what is disliked is unpleasant. Being apart from what is liked is unpleasant. Not getting what one wants is unpleasant. Identifying with the five aggregates of clinging (body, feelings, perceptions, mental formations (thoughts), sense-consciousness) is also dissatisfying, because they are always changing. The aggregates (khandas) are insubstantial, impermanent, uncertain and empty of self. This is what needs to be understood.
The cause of suffering is craving. The Pali word tanha (thirst) is used for this. And it is important to note that there is such a thing as chanda (right desire). Not all desire is to be abandoned. Chanda is the word used to describe right desire (desire that helps to put an end to suffering); and tanha is used to describe wrong desire, that which causes suffering.
The fading away and cessation of craving is what ends suffering. With wisdom one stops following the craving, and clinging to that which is insubstantial. The involuntary movements of the mind stop and there is an unshakeable peace. One is no longer harrassed and driven by craving and the worldly winds, which brings relief and freedom to the mind.
The Buddha listed the three right intentions above as being thoughts that he did not regret having, these intentions do not lead to unwholesome actions, they lead to good kamma and to nibanna.
The Buddha before his enlightenment divided his thoughts up to those that he regretted having (unwholesome thoughts); and those that he did not regret having (wholesome thoughts). He worked to abandon the unwholesome thoughts, dismissing them until they no longer arose. And he encouraged and cultivated the wholesome thoughts till they happened naturally, automatically without him needing to apply any more effort. He said the experiment worked and eventually his mind was filled with thoughts he didn't regret having. This made it easier then to settle into meditation.
To make a living that does not cause harm to oneself or others.
Needs to be tuned so it is neither too tight, nor too loose. I.e. don't burn yourself out, but also don't get lazy.
The four right efforts are:
1. prevention of unwholesome states of mind from arising. (By avoiding unwise attention to the fault; and unwise attention to the beautiful.)
2. abandonment of unwholesome states of mind should they arise.
3. generating wholesome states of mind.
4. sustaining those wholesome states of mind.
Unwholesome states of mind are the five hindrances: greed, aversion, sloth, restlessness, doubt.
Wholesome states of mind are the seven factors of enlightenment: mindfulness, investigation of phenomena (dhamma), energy (effort), joy, calmness, samhadi, equanimity (balance).
This is the four foundations of mindfulness.
Mindfulness of the body.
Mindfulness of feelings. (pleasant, neutral, or unpleasant).
Mindfulness of mental states.
Mindfulness of dhammas (teachings).
The body is in the mind.
A meditation object is used to calm and centre the mind, gather it together and bring it into unity and balance. Common meditation objects used are the breath, natural elements, primary colours, perception of light, or the emotion of goodwill (metta).
The Buddha classifies right samhadi as the four jhanas.
'Having gone somewhere quiet, away from distractions. Having removed longing and dejection in regard to the world, setting mindfulness before one.
The continuous practise of jhana gradually weakens the hold of greed and hatred on the mind until eventually those defilements fall away for good and never return. When this happens one becomes a non-returner, (the third stage of enlightenment) and is never again born into this world.
Full enlightenment (fourth and final stage) is the realisation of nibanna, and the complete end of the conceit 'I am' and delusion.