If anyone has a real desire to be a Muslim and has full conviction and strong belief that Islam is the true religion of God, then, all one needs to do is pronounce the “Shahadah”, the testimony of faith, without further delay. The “Shahadah” is the first and most important of the five pillars of Islam.
When should you say your Shahadah? My general answer to this is ‘when your heart feels at peace with your decision’. That will be the time that God has opened your heart and allowed it to know that you are ready to do it. At this time you will be surer than you’ve been of anything that this is the right time.