Excellent questions, Ed.
When we enter the ethos of the New Testament, we discover that the sharing of the Gospel is something quite natural and spontaneous. When people get healed by Jesus, they talk about Him; He can’t shut them up!
In the Book of Acts, we see the pattern continue. When Peter and John are hauled before the religious leaders and told not to speak of Jesus, they reply, “We cannot help speaking about what we have seen and heard” (Acts 4:18).
Laypeople also are communicators. “Those who had been scattered by the persecution in connection with Stephen traveled as far as Phoenicia, Cyprus, and Antioch, telling the message” (Acts 11:19).
In other words, whether Apostles (“professional preachers/missionaries”) or lay people, if they have experienced the goodness of God they want to talk about it.
Michael Green in his book, Evangelism in the Early Church, has documented many illustrations of how Christians in the earliest days of the Church’s experience, in humble, simple, but powerful ways, “gossiped the Gospel” in the midst of their daily work, and also used hospitality to good effect.
When you refer to “tentmakers,” it is not clear to me whether you mean in a technical sense (those who move cross-culturally to be a witness in countries of difficult access by means of secular employment) or the experience of being a Christian layperson anywhere, including right here in the U.S.
In either of these contexts, one has to work hard to make a living, leaving relatively little time to have “ministry.”
The philosophy of the organization whose article you cite (“Global Opportunities”) is that “ministry” is done by the quality of life while “on the job,” speaking when one has an opportunity.
The nature of one’s occupation and certainly one’s personality will influence the opportune moments and the style of communication.
Referring once again to the website, but this time to the article, Why do Christians Find Evangelism so Difficult, Dave English makes a helpful distinction between “hunting” and “fishing,” I quote two paragraphs which I found germane to your questions (see below)
May the Lord guide you both as you grow in your capacity to serve the Lord as busy laypersons, and may your lives and your words lead people to Jesus.
The approach in Scripture is to fish out seekers from among other non-believers and focus on them.
" But how do we spot seekers? By their questions.
" How do we get people to ask questions?
By our wholesome, attractive Christian lifestyle and our occasional fitting words about the Lord.
In the ocean of this world's people each of us is assigned to certain ponds--our extended family, our neighborhood, our workplace or campus, our professional circles and social clubs--wherever non-believers have a sustained opportunity to observe our lives. The gospel must be seen as well as heard.
What is the bait that lures seekers? Paul emphasizes four things.
1. Personal integrity, honesty, truthfulness, patience, moral purity, etc.
2. Quality work at our places of employment, as though our employer were Jesus Christ himself! Wholehearted, conscientious, thorough, creative work.
3. Caring relationships with people around us, especially hurting people--giving not just the gospel, but ourselves as well.
4. Fitting comments about God--not punctuating every sentence with religion, but saying the appropriate words at the right time.
(Dave English Why do Christians Find Evangelism so Difficult? Global Opportunities. http://www.globalopps.org, emphases mine.)