If you want to convert an Atheist your task should be simple. Atheists believe in evidence; our opinions are based on it and when the evidence changes, or we discover new evidence, we change our opinions. We have no sacred dogmas which can't be questioned; no tenets of 'faith' to which we must subscribe.
This should make us very easy to convert with the following three-step process:
- Produce the evidence that you found convincing.
- Explain why it 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.
- 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.
Now, since, presumably, you were convinced of your god's existence by just such evidence and just such a process, it shouldn't be too difficult to tell us Atheists where it's to be found and how it meets the above criteria.
In your own time....