When I was a travelling evangelist, I encouraged people to repent. 'Course, I'm a little old fashioned...I still believe in sinners kneeling at the mourners bench and praying through with tears of repentance until they know.... let me emhasize that ....THEY
KNOW... they have passed from death unto life and the Lord has forgiven their sins. They know because God changes them completely and makes them new creatures in Christ. They don't have to be told their sins are forgiven- they know it. Afterwards, I tell them they should make a public confession of their new found faith in God by being baptized in water in the Name of Jesus Christ. They are encouraged to seek the Lord until He fills them with His free gift of the Holy Ghost as in
Acts 2:4.
I don't present water/Spirit baptism as absolutely must do, necessities that "if you don't do it, you're gonna burn in hell"- I present water/Spirit baptism as incredible, God-given gifts to deepen ones walk with God.
No, I haven't used the "Sinners Prayer", though I have guided some who didn't know how to pray.