another way from Ajahn Buddhadasa:
*…But in the field of practice, the Paticcasamuppada is, as the Buddha said, just a handful. When there is contact with forms, sounds, odors, flavors, or whatever at one of the sense doors, that contact is called in Pali phassa. This phassa develops into vedana (feeling). Vedana develops into tanha (craving). Tanha develops into upadana (clinging). Upadana develops into bhava (becoming). Bhava develops into jati, which is “birth”, and following on from birth there is the suffering of old age, sickness and death, which are Dukkha.
Please see that as soon as there is contact with a sense object there is phassa, and that the subsequent development of phassa into vedana, tanha and so on is called Paticcasamuppada i.e. the process by which various things, existing in dependence on one thing, condition the arising of another thing, which in turn conditions the development of a further thing, and so on. This process or state is called Paticcasamuppada. It is dependent arising with no self or “me” found, merely dependence followed by arising.
The way of making use of it is not to allow the dependent arising to take place; cutting it off right at the moment of sense-contact, not allowing the development of vedana, not allowing feelings of satisfaction or dissatisfaction to arise. When there is no production of vedana, then there is no birth of the craving and clinging that is the “I” and “mine”. The “I” and “mine” lie right there at the birth of the craving and clinging; illusion lies right there. If at the moment of sense-contact when there is nothing but phassa, it is stopped just there, there is no way for “I” and “mine” to arise in truth-discerning awareness.
Another method: For the average person, it is extremely difficult to prevent phassa from developing into vedana. As soon as there is sense-contact, the feelings of satisfaction or dissatisfaction always follow immediately. It doesn’t stop at phassa because there as never been any training in Dhamma. But, when vedana has already developed, when there are already feelings of satisfaction and dissatisfaction, stop it right there. Let feeling remain as merely feeling and let it pass away. Don’t allow the reaction to go on and become tanha, wanting this and that in response to the satisfaction or dissatisfaction. Because, if there is satisfaction, then there will be desire, craving, indulgence, possessiveness, envy etc. in consequence. Once there is dissatisfaction, then there is the desire to beat to death, to devastate, and kill. If there are these sorts of desires on the mind, it means that vedana has already developed into tanha. If so, then you must suffer the spiritual disease of Dukkha and nobody can help. All the gods together cannot help. The Buddha said that even he could not help. He has no power over the laws of nature, he is merely one who reveals them so that others can practice in accordance with them. If one practices wrongly one must have Dukkha. If one practices correctly, one has no Dukkha. Thus it is said that if vedana has developed into tanha then nobody can help. As soon as any form of craving has arisen then nobody can help and there will inevitably be Dukkha.
In that turbulent wanting that arises in the mind, see how to distinguish the feeling of the desirer “I”, of the self that wants this or wants that, wants to do it like this or like that, or who has acted in this way or that way, or has received the results of those actions. That one who desires is “I”; wanting things, it grasps them as “mine” in one way or another -as “my” status, my property, “my” victory, “my” ideas and opinions - and in all of those feelings the “I” is present.
The feeling of “I” and “mine” is called upadana, and arises from tanha. tanha develops into upadana. If the Paticcasamuppada has progressed as far as tanha and upadana, the germ that enters through the ear, eye, nose, tongue or body has matured to the extent that it can express itself as the symptoms of the disease, because upadana is followed by bhava. Bhava means “having and being”. The having and being of what? The having and being of “I” and “mine”. Kammabhava is the action that conditions the arising of “I” and “mine”. If it is simply “bhava”, it means the condition of “I” and “mine” full-blown, the disease full-blown.*