How do I invite non-Muslims to Islam?

Calling to Allah is an obligation upon every Muslim according to their capacity, based on Allah's saying: ﴿Say, "This is my way; I invite to Allah with insight, I and those who follow me."﴾ [Yusuf:108], and the Prophet's (peace be upon him) saying: "Let the present convey to the absent."

The call must be with wisdom, good counsel, and disputation in the best manner. The caller must adopt appropriate means to address those being called. With the People of the Book, disputation should be in the best manner, by first mentioning points of agreement, then discussing points of difference, as in Allah's saying: ﴿O People of the Scripture, do not exaggerate in your religion or state about Allah except the truth.﴾ [An-Nisa:171].

As for polytheists, it is necessary to explain that Allah Almighty is the Creator with rational proofs, and that humanity was created to worship Allah alone, and that He has subjected to them what is in the heavens and on earth.

The call should be gradual until the one being called is convinced. As for the general Muslim populace, their call should be through good morals and upright conduct.