When you share your experience of believing in Jesus with a person watch for a change in his or her facial expression. Read it. If it is a softening go further. Ask them then if they would like to receive the gift of eternal life from Jesus. If they say yes, then guide them in what to pray. It would be something like this:
You: "Are you ready to pray to Jesus and ask Him to come into your life (heart)?"
You: "Then bow your head and say these words to Jesus. Repeat after me but don't say the words to me. Say them to Jesus Christ, okay?"
You: "Dear Jesus."
Them: "Dear Jesus."
You: "I admit I am a sinner."
Them: "I admit I am a sinner."
You: "I believe you died on the cross for me and rose again."
Them: "I believe you died on the cross for me and rose again."
You: "Come into my heart and save me."
Them: "Come into my heart and save me."
At this point watch their facial expression to see if there is any indication of them experiencing the entrance of Christ into their heart (you don't have to close your eyes as you lead them in prayer). Sometimes a facial expression will change, however subtle. Then close the prayer:
You: "Thank you Jesus for saving me."
Them: "Thank you Jesus for saving me."
Now, wait until they look at you and then ask them if Jesus came into their heart. They usually say yes. If they say no you can question them and try to draw them out with more information. If they will not talk or cannot attest to the fact that Jesus came into their heart thank them for listening to you. Then change the subject and talk about something else. This helps bring closure to the session.
Bring the new believer to church with you and help them understand baptism. Encourage them to be baptized as public testimony and in obedience to Christ. The church, a.k.a. the Assembly or Fellowship, is where we as His body meet with Jesus. The church can do many things including encouraging witnesses and training evangelists. It encourages and prays. It also teaches and trains. It disciplines.
How does evangelism result from Christians being involved in the marketplace of life, that is, while working, shopping, voting, taking a walk in the park, etc.? Followers of Jesus behave differently than regular people (or they should). This is not a consciouse thing. Christians have little awareness that they stand out in a subtle but evident way. They stand out because they have the peace of God in their hearts and march to a different drumbeat. This difference attracts attention from other people, subtle attention.
Others watch it at first. They talk together about the Christian. Then they might approach and get to know the Christian for one compelling reason: to discover what is different about him or her.
In post-Christian America, if a fellow employee asks you about why you are exhibiting a peacefulness or "why you are different," it is not harassment to share your life change experience about when you met Jesus. It is not against most company policies because the policy wonks do not think about these things. They deal in general terms like harassment, bullying, etc.
Do not skip assigned work to talk about your faith. Keeping it short means you have prepared something effective to share before you are in a situation to do it. So think about an effective "water-cooler speech" about your faith that makes sense to a person who does not know the Bible.
Wait for a natural segway. Sometimes starting with a tease and then walking away is a nice way to raise interest. Say something like, "No, I'm not worried about layoffs, I've found a peace and confidence that gets me through whatever life throws at me!"
You may find that--more often than most Christians know--the non-believers have actually sensed an aura of peace in the Christian colleague which serves as a draw. In particular, they especially notice those mature Christians who have grasped the full meaning of salvation, which is to die to self and be alive in Christ. If you are a Christian who yells, fights, and cusses, I'm glad they don't ask you!
If the churches were to transition to old-time evangelism, to this ancient model of person-to-person evangelism in the marketplace, it would be a paradigm shift for most churches and their members. Most Christians are not equipped to do it. This should be a concern to church leaders. This problem can be addressed by those who can do it. They can model the doing of evangelism--often by taking someone with them to watch--and they also give lessons to others about how to model the Christian life and then share the Gospel. With God nothing is impossible. And I assume that each of us can still choose to use these "always modern yet old-time-evangelism techniques" to help others encounter Jesus.##