This should make us very easy to convert.
All you need is authenticated, incontrovertible evidence that your god exists and your evidence only needs to pass a few simple tests which, presumably, you believe it's already passed
- You will need to explain why your evidence is evidence ONLY for your god and not any other. Since people have believed in over 3000 different gods in recorded human history, obviously you will need to show why your evidence couldn't be evidence for any of those.
- You will also need to explain how a god is the ONLY possible explanation for your evidence and why it can't possibly be explained as the result of a natural process.
In your own time....
(p.s. Opinion isn't evidence and nor is a quote from a book unless the quote refers to authenticated, observable evidence meeting the above criteria).
[Later note] It seems many Creationists are unsure of what constitutes 'evidence' and imagine it includes ignorance and even the opinions of others. The following blogs may help them gain the necessary understanding to be able to use the above method:
(Thanks to @kaimatai on Twitter for providing these helpful link)