FYI- you will need to be registered for employment with the Board of Education and Immigration. You will need to fulfill requirements such as health checks. These are mandatory. Otherwise, you are working illegally. Just like any other foreigner meeting the requirements, there are no shortcuts to working here.
I haven't heard of anybody actually caught working illegally off a post here, but there is always a first time. I was caught and fined 4m, due to not being registered by an employer some years ago. I know how it felt and the cost. Thankfully, I was not deported, as they felt it was not my error. But, play it safe.