Hearing the word of God, believing the gospel and in Jesus as the Son of God, repenting of one's sin and confessing their belief in Jesus are necessary, but they only take one unto salvation. In order for one to get into Jesus Christ where salvation is found they must be baptized for the remission of their sins. I've published an extensive study on baptism elsewhere on this site. Please follow the link to learn more about baptism and its role in our salvation.