There are many methods that have been used throughout history. For your personal beliefs, what do you feel is the 1) most effective method of providing religion to others, 2) the proper (or moral) method and 3) your own personal method?
(1) Methods come and go. In North America, we're addicted to technique and rational process, which makes questions of "effective method" make sense. There's no such beast, though.
Besides, there's the very difficult question of
how to measure effectiveness. At a Billy Graham crusade, they would count the number of people who "came forward" and said a "sinner's prayer". Well, does a person saying a sinner's prayer count as an effective provision of religion to a person? Has the person who said a sinner's prayer actually adopted the religion espoused by Graham?
Most of us, on reflection, say "no." There must be more. But what does that "more" consist in? Christians would generally say the more is discipleship. That is, a person must be trained in the faith -- its beliefs and practices. In traditional churches, that's what catechism is for, and when the candidate completes her catechism, she is eligible for baptism/confirmation. But again, we have to ask, if a person has undergone catechism and has received baptism, does this count as an "effective" provision of religion to a person? Has the person who has been baptized/confirmed actually adopted Christianity?
Most of us, on reflection, would say "it depends." Depends on what, though? Sincerity? How do you measure that? By continued profession of faith and participation in the community? Can't a person do all that without, in their hearts, believing? Does it matter what's in the heart? Is the ceremony enough? Opinions differ. But most would probably say that a good track record of participation in the religious community and adherence to the beliefs and practices of that community are at least the measurable signs of adopting a religion. So perhaps we'd best stick with that.
But then it's obvious that we can't just count conversions and baptisms to get our statistics to measure our effectiveness. The processes of adopting (or conversely, conferring) a religion are complex and convoluted. So measuring their effectiveness may not be really possible.
(2) and (3) Given the complexity of conversion (and I can only speak to the Christian case), the only method that makes sense to me is "induction." That is, I introduce the beliefs and spiritual practices of Christianity to those who are interested. I don't hold crusades or mass rallies (although there may be a place for those -- God knows -- it's just not my style). Rather, I let those around me know of my Christian profession and then let it be. I've found that if you let people know your general religious perspective, it eventually issues in discussions, comparisons, and so forth, all of which is healthy. If in the course of those discussions a person is sufficiently interested in Christianity, I offer to introduce some Christian practices. If the person responds favorably, I introduce more, eventually introducing them to corporate practices such as worship. If the person decides to go even further, I arrange for them to take catechism classes. By that time, the candidate has had a fairly full introduction to Christianity and is well-placed to decide whether this is the life they want to adopt or not.
In my whole life, I have seen only one person make it through the whole process (although there may have been others who completed it through other people that I don't know about). I tend to teach people about the whole faith, including those bits that are likely to turn people off, such as the high moral standards they'll be expected to adhere to. I also don't shy away from the philosophical issues raised by faith in general and Christian faith in particular. But that one person has stuck through some pretty serious times of testing. So I'd count that a success. Others who use a more streamlined practice see more "success" in terms of numbers who say sinners prayers or get baptized. I can't say for sure whether they're actually more successful or effective than me.
It seems to me that although method may be important, the most important factor in Christian conversion (from a Christian perspective) is the action of the Holy Spirit. He blows where he wills, and if he's not blowing where I'm sailing, then my efforts are in vain. If he's blowing where I'm sailing, then there's little I can do to fail. So a large part of my process involves private prayer. Nevertheless, as a part of a faithful (I don't say effective) Christian witness, I owe it to seekers to present Christianity as fully and as fairly as I know how. I think my method does so, but I'm open to revision.