There are no rituals or baptism to become a Muslim. It is a simple declaration, preferably in the presence of two witnesses. This must not be done through force, as it is a declaration out of a person’s conviction that there is only one Creator of the universe, i.e. the God of Abraham.
Any one who wants to accept Islam, and become a Muslim will be required to say the following:
I testify to the fact that there is no deity deserving of worship but Allah, and I testify to the fact that Muhammad is the Messenger of Allah.
Some people believe that when one makes this declaration he/she must immediately become an ideal Muslim. It is necessary to know that it takes time to learn all that is necessary for a Muslim to know and practice, so that, after the declaration of Faith, the new comer to Islam will learn how to pray and fast, etc.
Upon declaring the shahadah, as it is called, a person becomes a brother or sister in faith; and will be treated as such by every Muslim.
To change ones faith and belief is a very courageous thing, but if a person is convinced that there is only one Creator of the universe, i.e. the God of Abraham, then he/she should not hesitate but declare his/her belief in that God.
Because it requires courage and will to do so, the Prophet (pbuh) reports that anyone who accepts Islam, will have all his/her past sins forgiven.