Often it is important for a soul winner to know what a person really believes before presenting the gospel. There is a great way to find out where the people you touch really stand. It is a question that I borrowed, and used for many years with Catholics in Italy. You can find out what a person believes about his salvation by asking this easy question:
"If someone came to you and asked, 'How can I get to heaven?' What would you tell him?"
This is a "what if" question that does not put him on the spot about whether he himself will get to heaven, so it is non-threatening and easy for him to answer. Unless his answer is about how Jesus Christ saves, you have good news for him, and will want to tell him so. First, though, to make sure that both he and you have understood what he really believes, repeat his answer using different words, so he can correct any misunderstanding.
Without the help of this question, as you present the gospel, many will interpret what you say in a way that will fit with what they have always believed. When you finish presenting the gospel they will respond, "Oh, I have always believed in Christ!" On the other hand, when they have just told you what they really believe, they can understand how it differs from what you have presented from God's word. Now they can seriously consider the salvation Christ offers.
God does not stand in awe of people of global importance like the pope. He loves the little guys and gals you and I meet, and is "not willing that any should perish, but that all should come to repentance" (2 Peter 3:9). He wants to reach out to people through us.
Two books that will help you reach Catholics for Christ are: Answers to my Catholic Friends and Understanding Roman Catholicism.