I'm not a native speaker, and I trust since you've been living in Australia for so many years, your English is definitely better than mine. I just hope that you can correct my 'correction'.

Can someone be a good teacher without being trained to teach?

How to correct correctly?

I like this site -- actually, I adore it.

One of the activities I enjoy the most is making corrections. It allows me to do one of the most favourite things I have done in my life: playing with the English language.

'Most favourite' is incorrect. There's nothing 'more wrong' than it, and 'more wrong' itself is incorrect. They're both 'very wrong'.

It seems this interest (Be clearer, otherwise referencing can be confusing.) has been with me since a very early age, although it has also gone through long periods of latency as my life changed and turned in different directions and into different circumstances. When I was in school many years ago I remember a guy coming up to me with a scribbled love letter that he wanted to give to a girl he admired. He thought it was written very badly so he showed it to me seeking an opinion. I re-wrote it for him – something that seemed very natural for me – and he walked away feeling amazed and very happy. I’m not sure how things went with him and the girl but I do remember the experience vividly; I can even now still see his messy handwriting and spelling mistakes as a distant image in my mind.

So it’s no surprise to me that many years later I have become so absorbed in doing a similar thing here on italki.

However, I am not a qualified teacher: I’m just someone who loves language. I also understand that to teach effectively there are certain techniques and principles which I should follow, and I’m hoping that I will learn some of these while I am here. I also wonder, though, if in some way I am already applying some of the techniques and principles in an unconscious way, but I don't really know this because I’ve never been trained to teach.

I think you need a pair of commas around 'though'. Otherwise, it requires much more effort to understand that sentence. Another suggestion is to simply delete 'though'. You don't really appear to need it.

And so I am lead back to my original title and question.

Can someone be a good teacher without being trained to teach?

I welcome anyone, teachers and student alike who are interested in this question, and are willing to offer their thoughts and ideas, and in particular I would greatly appreciate any constructive criticism.

No comma after alike. If you add the comma, you're suggesting each and every teacher and student is interested in the question and can offer you ideas. Another alternative way to avoid this is to use 'that'.

You are also welcome to browse any of the corrections I have made and tell me if you think they are effective or not. I want to be able to share the knowledge, and I will do it better if people can share their knowledge with me.