Yoga as Meditation on Kṛṣṇa
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chanting, are considered the most important. At a public  kīrtana  one person can chant Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/ Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare, while a group listens, and at the end of the  mantra , the group can respond, and in this way there is a reciprocation of hearing and chanting. This can easily be performed in one's own home, with a small group of friends or with many people in a large public place. One may attempt to practice meditational  yoga  in a large city or in a society, but one must understand that this is one's own concoction and is not the method recommended in  Bhagavad-gītā .
The whole process of the  yoga  system is to purify oneself. And what is this purification? Purification ensues upon the realization of one's actual identity. Purification is realizing that "I am pure spirit—I am not this matter." Due to material contact, we are identifying ourselves with matter, and we are thinking, "I am this body." But in order to perform real  yoga  one must realize his constitutional position as being distinct from matter. The purpose of seeking out a secluded place and executing the meditational process is to come to this understanding. It is not possible to come to this understanding if one executes the process improperly. In any case, this is the consideration of Lord Caitanya Mahāprabhu:
harer nāma harer nāma 
  harer nāmaiva kevalam 
  kalau nāsty eva nāsty eva 
  nāsty eva gatir anyathā