What is the recommended manner of speech and demeanor for the preacher?

Primary text

It is recommended that the preacher speak deliberately, clearly, and articulate, avoiding excessive haste or drawn-out speech. Furthermore, the preacher must be humble and heed the admonition he delivers to the people. This is based on the report that the Prophet, peace be upon him, saw people whose lips were being cut with scissors of fire, and it was informed that these were preachers from his community who preached what they did not practice.