1. Speak with Vedic Evidence, then it is solid

    …without reference to the Vedic literature, anything you speak, it has no ground. Sruti-pramana, this is Vedic culture, sruti pramana. It must be supported by sruti. In Caitanya-caritamrta you'll find whenever Sri Caitanya Mahaprabhu says, He gives immediately Vedic evidence, sruti-pramana. Then it is solid.

    Srila Prabhupada — August 12, 1976, Tehran