Only those who are children of God can be baptized. A person must be saved, born again, before he can be baptized. Jesus was never lost, therefore He did not need to be saved. He was already the only begotten Son of God. All others must be saved before they can be baptized.
Scriptural baptism is believers' baptism.
Pouring and sprinkling cannot be scriptural methods, because neither one can be found in the Bible. Immersion in water is the only scriptural method of baptism. Jesus was immersed. Sprinkling requires little water. Baptist pictures a burial, and sprinkling could never do this.