First, they did most of their evangelism on what we would call secular ground. You find them in the laundries, at the street corners and in the wine bars talking about Jesus to all who would listen. Although it was impossible for them to hold large rallies, which would have fallen under an imperial ban, we get the impression that they had a penchant for small open-air meetings. Gathering a small crowd they spoke as warmly, thoughtfully and challengingly as they could. It is fairly common in the Acts; common too in the second century. It is salutary to recall that the early Christians had no churches during the first two centuries, the time of their major expansion. They had perforce to use the open air. Today open-air evangelism has been largely discredited. But it is my experience that it can be recovered if it is done with humour and lightness of touch. It helps a lot to have a team of people working together. It helps to use drama, dance, juggling and other art forms to help people see as well as hear. I have sometimes seen people come to a deliberate commitment to Christ through such meetings. More frequently, however, it starts a process which is carried through later with proper instruction which is naturally impossible in the open air. Moreover if it is done well, it fascinates a wider circle of passers-by, and at least sends them away with the impression that these Christians have got something sufficiently exciting to spur them to face ridicule. And that might prove the beginning of a quest.
Michael Green. Evangelism In The Early Church (p. 23). Kindle Edition.