Before entering the first dhyana, one must use the Five Methods of Stilling the Mind and the Four Foundations of Mindfulness. Seeking and waiting are present during the first dhyana, and persist after leaving the first dhyana. Prior to entering the second dhyana, the dhyana of in-between, there is only seeking but no waiting.
In the second dhyana, there is neither seeking nor waiting. Only enjoyment, bliss, oneness, and putting down remain. One lets go of everything, including ideas of existence and emptiness, and continues practicing to attain enlightenment.
The Fourth Dhyana Level
The fourth dhyana is the dhyana of the Mahayana, also known as the dhyana of the bodhisattva. The main difference between the dhyana of the Hinayana and the Mahayana lies in the meaning of liberation. Hinayana practice is for the sake of liberation from the three realms of existence.4 According to the dhyana of the Mahayana, transcendence means neither attaching to, nor fearing the cycle of birth and death, and this distinguishes it from the Hinayana.
Not attached to birth and death, one does not fear birth and death and will have the compassion to return to the world to deliver sentient beings. Could one at this stage be practicing the four dhyanas and eight samadhis? Of course one could, as those are among many methods for attaining transcendence. For example, sitting meditation is one of the practices in the dhyana of Mahayana, but is only one gate of entry. In fact, one can be practicing in any situation-reading and reciting sutras, prostrating, walking meditation, or engaging in any task or work as long as one's mind is concentrated on the task at hand. One can be doing anything and still be practicing.