John the Baptist's methods as recorded in scripture are descriptive - i.e. that is historically what he did as a uniquely commisioned prophet stradeling the OT and NT eras.
As for how believers are generally to share truth scripture tells us (prescriptive as the norm): "Always be prepared to give an answer to everyone who asks you to give the reason for the hope that you have. But do this with gentleness and respect..." (1 Peter 3:15) and, "Let your speech always be gracious, seasoned with salt, so that you may know how to answer everyone." (Collosians 4:6) and, "The Lord's servant must not be quarrelsome but must be kind to everyone, able to teach, not resentful. Opponents must be gently instructed, in the hope that God will grant them repentance leading them to a knowledge of the truth..." (2 Timothy 2:24, 25)