What are the conditions necessary for Nibbana?

I can’t disagree with any others answers advocating this or that practice. But what jumps to my mind is the Buddhist teaching all conditioned things - those arising from causes* and conditions are impermanent. Thus ultimate extinguishing, Nimbanna, is beyond conditions or causes. But, as one uses a raft to cross a river and then abandons it, causes and conditions may be used to reach the unconditioned, and uncaused, which I think cannot be spoken of, or should not if it could be.

One who attains Nibbana has extinguished ten fetters:

“Bhikkhus, there are these ten fetters. What ten? The five lower fetters and the five higher fetters. And what are the five lower fetters? Personal-existence view, doubt, wrong grasp of behavior and observances, sensual desire, and ill will. These are the five lower fetters. And what are the five higher fetters? Lust for form, lust for the formless, conceit, restlessness, and ignorance. These are the five higher fetters. These, bhikkhus, are the ten fetters.”

-- AN 10.13

To extinguish these fetters, one practices the eightfold path. Or, more comprehensively, one practices and fulfills all factors of the Bodhipakkhiyādhammā.

Question does not apply. Nibbana is unconditioned, uncaused, unmade. The proper question would be what are the conditions for cessation of All/aggrigates

The condition for Nirvana is "suchness". The condition for suchness is having no conflict between "is" and "should". The condition for no conflict is insight into the nature of things. The condition for insight is study and practice of Noble Eightfold Path.

A slightly cheeky thought: it's not about fulfilling conditions, but rather removing conditions. In practice, cultivating good conditions yields good results (and thus this is prescribed as part of the path), but ultimately the unconditioned needs no conditions. When a fire burns out because its fuel is exhausted, it vanishes. All that remains is the vanishing.

As Upasak inb4dead told.

There are no conditions for Nibbana. Nibbana is unconditioned.

To possible reach the Unconditioned, one needs to hold on, put into, increase the conditions to let go of them.

One needs to have upanissaya (strong conditions) and give into strong condition causes (upanissayapaccayena). Of which causes are conductive and which not, how to foster, increase, develop... conductive causes, all of that is what the whole teaching are about.

The Essence of the Dhamma might be useful, since the Unconditioned is not to be reached without giving conditions to attain.

[Note: This is a gift of Dhamma, not meant for commercial use or other lower wordily gains by ways of exchange or trade]

The experience of nibbana for the first time happens at the first stage of awakening, other wise known as stream entry.

The practices leading to stream entry are encapsulated in four factors:

Association with people of integrity is a factor for stream-entry.
Listening to the true Dhamma is a factor for stream-entry.
Appropriate attention is a factor for stream-entry.
Practice in accordance with the Dhamma is a factor for stream-entry.

— SN 55.5

The practice leading to disenchantment, dispassion, and release follows a stepwise path of cause and effect.

"Now, I tell you, clear knowing & release have their nutriment. They are not without nutriment. And what is their nutriment? The seven factors for awakening... And what is the nutriment for the seven factors for awakening? The four establishings of mindfulness... And what is the nutriment for the four establishings of mindfulness? The three forms of right conduct... And what is the nutriment for the three forms of right conduct? Restraint of the senses... And what is the nutriment for restraint of the senses? Mindfulness & alertness... And what is the nutriment for mindfulness & alertness? Appropriate attention... And what is the nutriment for appropriate attention? Conviction... And what is the nutriment for conviction? Hearing the true Dhamma... And what is the nutriment for hearing the true Dhamma? Associating with people who are truly good...

https://www.accesstoinsight.org/lib/study/into_the_stream.html

From a Theravada perspective, in order to attain Nibbana (the fourth and final stage of enlightenment), you generally need to pass through the first stage of enlightenment, which is the fruit of stream entry.

In this YouTube video, Ven. Dhammavuddho explains the characteristics of a sotapanna (stream winner) and explains how to get there. He quotes from many suttas to support his points.