Don’t let the common philosophy of “relationship evangelism” steal your zeal. This is the idea that you must befriend people and build a relationship before witnessing to them. If you believe that, consider two questions. First, who are the hardest people to witness to? Isn’t it your unsaved relatives? Why then would we want to wait until we build relationships with people before witnessing to them? If we witness to strangers and offend them, we lose nothing. But if we have developed a good relationship with a person and offend him, we risk losing that relationship. Building relationships actually makes it harder to witness. The truth is, we often will use any excuse not to confront people with the offense of the cross, and building a rapport with them is less threatening than sharing the truth of the gospel.
The second question is, what happens to people if they die while you are taking the time to build relationships with them? There is no nice way to put it—they will go to hell for eternity if they die in their sins. They will end up in the lake of fire, so how can you even consider taking that risk?
So make it easier on yourself. Witness to strangers. Make it a way of life to witness to people you don’t know, and if you must build a relationship with them, feel at liberty to build for 3 or 4 minutes until the relationship grows, then share the truth, as you should.
1 Thessalonians 2:8 So, affectionately longing for you, we were well pleased to impart to you not only the gospel of God, but also our own lives, because you had become dear to us.
Ray Comfort's Daily Evidence 
It seems that as Jesus first calls, and then builds a relationship, we should do the same. He first called the twelve, then spent years building a relationship. He first called me, and now takes the time to build that relationship. We also should let Him use us to first call the lost to Him, and then spend time building that relationship through discipleship. Relationship is so important, but sharing the gospel must be first and foremost and cannot be hindered by feeling the need to form some kind of relationship before offering His gift of salvation. Hadn’t thought about this before your post. Thanks for sharing 🙂
Or… how about witnessing daily as directed by the Holy Spirit? Sometimes we will be called to use words and speak to strangers…but always we will be called to witness through deeds,small & large, that make up our lifestyle, daily choices and attitude of heart. I don’t believe that walking by faith, means following a set system or method. The life of Christ was based on doing what the Father directed Him to do….some days it was healing a multitude of people and another time it was healing only one within a multitude. For me, daily surrender keeps me dependent upon Him and less likely to think that “I” am needed to save anyone.