We have found that using questions throughout a conversation when presenting the gospel is one of the most effective ways for people to come to a clearer and deeper understanding of how one can be saved. It's interactive for the listener and it provides opportunities to understand where the person is at with how much they have grasped the gospel.
The following are some examples of ways that you can use questions in your evangelism:
Should I ask someone whether they have sinned?
What are some good analogies to use for the gospel?
How do I check whether someone has really understood the gospel?
What should I do when someone is ready to trust in Jesus?