How can I sincerely call to Allah as a mosque preacher, and what are the best books to read?

Calling to Allah is the noblest of professions because it is the profession of the Messengers. Acquiring its virtues requires sincerity and truthfulness, not the pursuit of prestige or wealth. Allah Almighty said: (And who is better in speech than he who invites to Allah and does righteous deeds?). The Prophet, peace and blessings be upon him, said: "For Allah to guide a single man through you is better for you than red camels," and he said: "Whoever calls to guidance will have a reward like the rewards of those who follow him." He also warned against seeking knowledge for worldly gain. The caller (Da'ee) must be truthful and sincere to Allah to benefit himself and others. Among what is recommended to read are: the Book of Allah, reliable books of Tafsir (exegesis), authentic books of Hadith and their commentaries, and books on Fiqh (jurisprudence) and Seerah (Prophet's biography).