As far as Islam is concern, there are no complicated procedures for a person wishing to convert to Islam. First, the person needs to say the words of the Shahadah (i.e., Testimony) in front of some Muslims in addition to documenting his or her conversion in any local Islamic center.
On this issue, an Islamic scholar, Sheikh Ahmad Kutty, states:
Conversion to Islam is a simple procedure; it does not entail any complicated rituals or ceremonies, since Islam does not allow any intermediaries in worship, and as such there is no priestly class to administer specific rites. Therefore, conversion is mostly a person’s own choice; as long as he/she is willing to accept the basic tenets of faith. This must be done without any external coercion or pressure. As long as the person verbally expresses his or her belief in front of some Muslims his or her conversion is acceptable.
However, because of the need for documentation (in some places), it is best that the person goes to an Islamic center that can issue a certificate of conversion. To do this, the person has to book an appointment with the imam of the local mosque who would be more than willing to facilitate the conversion.
At the time of conversion, the person will be asked to repeat the following words of the Shahadah: Ashahadu anlaa ilaaha illa Allah wa ashahdu anna Muhammadan rasulul Allah (i.e., I bear witness that there is no god worthy of worship but Allah; I bear witness that Muhammad is the Messenger of Allah).
Besides, it is also good to affirm faith in the following tenets of Islam: I believe in Allah; in His angels; in His scriptures; His messengers; the Last Day and the fact that good and bad are decreed by Him. The person can request a certificate indicating the date of conversion as he or she may need it for purposes like pilgrimage to Makkah.
Finally, let me also suggest that the person consults the following excellent work entitled, “Complete Idiot’s Guide to Understanding Islam” by Yahya Emerick (2nd edition): It has all of the essential information a person may need to know about Islam.