Here is a re-post of a comment I made a few months ago.
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Speaking about Christ should be natural. He should be on our lips, both with and without trying.
>> Be prepared. The better you know Christ, the better witness. This will likely include knowing scripture, but a close personal relationship with the Lord is essential.
Added comment: Know what the unbeliever must understand and do to accept the Lord. He must recognize that God loves him. He must recognize that everyone has personalty fallen short (sinned against God) and are separated from Him. He must know that God became flesh in the person of Jesus Christ who bore the penalty for his sin. He must acknowledge all this as true and directly pertaining to him. He must then pray to have Jesus take over his life.
>> Coming from that close relationship with the Lord, should be your knowledge of what Christ has done in your life. Struggles you may have had that He saw you through, the peace you feel. A witness shares what he has personally experienced.
>> Have a strong prayer life. Confess your sins as soon as the Holy Spirit lays them upon your heart. Sharing must be done in His power, not yours. Unconfessed sin is an impediment to the Spirit working through you.
>> Remember, it is the Lord’s battle. You cannot make an unbeliever believe. It is the Lord that draws new believers, not Christians that push them.
>> Be of good reputation. Even if you are not saying “be a wonderful person, just like me”, the enemy will use any flaws that may have been noticed in your character to discredit your words.
>> Those around you should know you are a Christian. They should know this for two reasons.
1 The first is so that your life can be a witness to what living for Christ is.
2 The second reason is that it is much easier to talk about what Christ has done for you if they already know you are a believer. This doesn’t have to be overt or threatening. If you mention going to church; if they see you reading scripture during lunch then when the Holy Spirit leads you, there will not be a “coming out of the closet” feeling that the enemy sometimes uses.
>> As the Spirit leads (and prepares the potential brother), tell what Christ has done for you. From a spiritual standpoint, sinful actions are symptoms, not causes. Don’t be too concerned with fighting their sin. That’s not your responsibility. In reality, even if an unbeliever didn’t do any sinful actions, they would still be in need of Christ. Helping them fight their sin may be possible after they accept the Lord, but until they do, all they can do is sin.
>> You may be one of a series of events that work in another’s life to bring them to Christ. You are not responsible for results. You may not see the results.
>> Talk about what Christ has done for you, particularly in ways that may relate to the life of the potential convert.
>> If you think they ay be close to a decision, make sure you tell them that they must personally accept Christ and want Him to lead. If the person is coming to Christ because he realizes his sinful nature, make sure that they know that Christ has personally paid the price for that sin. If he is coming because he feels Christ’s love, make sure that he still knows that Christ paid the penalty for his sin and wants to work in their life.
>> If you are fortunate enough to be present when the convert gives his life to Christ, make sure that you encourage him to attend services and join a church. Ask him to come to church with you. Offer to study the Bible with him. You should also make sure they HAVE a Bible. If you cannot provide one, your church may be willing to help there.
>> Pray to the Lord on behalf of everyone you witness to.
>> In your prayerful meditation, review the events and ask the Holy Spirit to show you how to improve.
