I am seeing our church grow from relationships that have little or nothing to do with faith at the beginning of those relationships. An example is our church is in the middle of deep poverty for miles in every direction. We've learned many of our neighbors have "shopped" around various churches, most giving up. They don't know a bit of Bible, but witnessed a lot of religion, and religious people shunning them because they appear and act so differently. Most of the women only have a couple of nice clothes that fit, the men at best coming in blue jeans and maybe their best work shirt.
We have been growing a youth ministry in that area, our youth inviting kids at school to come eat pizza and watch a play they put on. Sooner or later a parent brings their kids for that, maybe staying to eat some pizza. When they come, all of us show love toward them, not expecting anything of them. We let them expect of us. What little most people expect of anyone claiming to be a Christian amounts to
1. Do we have good salt in us? They don't know what that means, but they do know how to taste salt, and detect true spiritual salt by it's effect on them.
2. Are we at peace with one another and with them?
3. Do they witness unfeigned love among us and toward them. They don't yet understand it, but love receiving it.
John 13:35 By this shall all men know that ye are my disciples, if ye have love one to another.
1 John 3: Hereby perceive we the love of God, because he laid down his life for us: and we ought to lay down our lives for the brethren.  But whoso hath this world's good, and seeth his brother have need, and shutteth up his bowels of compassion from him, how dwelleth the love of God in him?  My little children, let us not love in word, neither in tongue; but in deed and in truth.
All those relationships are unique and there's no way to "be prepared" for them. We do our part by being available to be used by God, then walking it out.
In time a father finally brings his wife to church. Eventually one or both take in
Sunday School, their children getting more involved. They begin taking in the word of God, realizing there's quite a lot to benefit by, from which grows the concept of faith. One by one they begin responding when realizing they need to be saved. God gives faith to believe, and that seed grows them to add faith into other areas such as relationships with other people, then applying faith to their own marriage relationship. That's the most difficult application of faith in couples that are apart from God or very new in the faith. Once that develops, then both faith and expectancy adds to the marriage and better training of children. What started out seemingly hopeless comes around to glory for Christ.
Be fishers of men