How one becomes guru? That is also very easy. Śrī Caitanya Mahāprabhu says, yāre dekha tāre kaha kṛṣṇa upadeśa (CC Madhya 7.128). You haven't got to manufacture anything. Simply you try to repeat the instruction of Bhagavad-gītā, kṛṣṇa upadeśa. Not only Bhagavad-gītā; there are many other instructions. Especially Bhagavad-gītā. So if you simply carry the message of Bhagavad-gītā, then you become guru. Don't manufacture anything. Then it will be spoiled. Simply stick primarily . . . Man-manā bhava mad-bhakto mad-yājī mām namaskuru (BG 18.65). You can . . . everyone can say this. Kṛṣṇa says that "You always think of Me." So you can repeat only. You can say to others, "My dear sir, please think of Kṛṣṇa." It doesn't require very much education. Simply just like a peon carry the message: "Sir, you always think of Kṛṣṇa." Man-manā. Then you become guru.
If you follow it strictly—you also think of Kṛṣṇa yourself, and you teach others, "My dear sir, my only request is that you think of Kṛṣṇa"—nobody will kill you. Everyone will . . . If he doesn't follow, he will appreciate you: "Oh, these sannyāsīs are very nice. They are advising to think of Kṛṣṇa." Then you become guru. Simple thing. Man-manā bhava mad-bhaktaḥ.