Conditions for valid marriage contract
Question

What is the correct Islamic procedure for a marriage ceremony, I mean if two Muslims are married (legally) without the presence of a religious "person" (like imam etc.), does that mean the marriage is non-existent in terms of Islam?
Praise be to Allah.All praise is due to Allaah. A marriage contract is valid in Islam if the following conditions are met, even if the marriage does not take place in a court, or in the presence of a Judge or the Imaam of the masjid. In addition, it does not need to be written. The waliy (guardian) of the girl has accepted the proposal by saying, for example, "I marry you my daughter", and the one who proposed has replied, for example, by " I accept," or "I am satisfied" (i.e. with his acceptance). This takes place in the presence of two witnesses The woman is legally eligible to marry the man according to Islamic shari'ah (that is she is not a Mahram of the proposer [those to whom the proposer is forbidden to marry. etc.]) Allah knows best.