I associate CS Lewis with the Top-Down strategy for becoming a Christian - the suggestion for What To Do when you want to become become a Christian but aren't yet a Christian.
Lewis's basic idea is that you start out by 'going through the motions' or (less charitably) 'pretending' to be a Christian; and the rest will follow.
So, for instance, you might start praying, reading scripture regularly, or attending church (he suggests the nearest church of your birth denomination - which made sense up to c.1955 but nowadays would be pretty hazardous in most cases). The idea is that by developing good habits on the surface, your deep convictions will be trained to follow.
If this works, then by all means do it! But I suspect that modernity has inoculated many people against any and all such surface approaches, because it has ensured that all information will be systematically misinterpreted. Plus leftist-materialism has so permeated all institutions that church services and scriptures (in new translations and commentaries) alike have been corrupted to work (overall) against Christianity - e.g. by presenting the religion as primarily 'about' social justice or the environment.
My alternative idea (expounded multiple times on this blog) is for individuals to discover and examine their own most fundamental assumptions about reality - their metaphysics.
These might include assumptions that there is no soul, that the spiritual realm is imaginary, that all talk of life after death is wishful thinking, that reality is a mixture of blind determinism and accident etc. Such assumptions (which are very common, but unfounded) will usually block conversion, so they probably need to be addressed.
By 'examine' these, I mean they should be made clear and brought before the intuition, the imagination - to see whether we really-and-truly and whole-heartedly endorse them as necessarily true... and if not, what instead we do endorse.
Such a process will, I think, lead most people to Christianity if pursued honestly and diligently - and will do so in a Bottom Up fashion, by building Christianity upon the foundations of what we feel-and-know to be true metaphysics.
