All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.
Da‘wah is an obligation on every Muslim, each according to his own capability. Allaah Says (what means): {Say, "This is my way; I invite to Allaah with insight, I and those who follow me.} [Quran 12:108]
Therefore, Da‘wah is an obligation on everyone who follows the Prophet, sallallaahu ‘alayhi wa sallam, because he, sallallaahu ‘alayhi wa sallam, ordered every Muslim to convey anything he learns from his Sunnah to those who have not heard it. [Al-Bukhari and Muslim]
The means and methods of Da‘wah vary from one person to another according to the environment, time and place each of them practices Da'wah. For information on the qualities of the person who practices Da'wah and the methods that one may adopt, please read Fatwa 85658.
Moreover, it is important to exert extra efforts in reading books that address Da‘wah, its methods and the qualities of those who practice it.
Allaah Knows best.