I am originally a tutor of high school (A - level, IB, AP, IGCSE ) maths and physics. However I am kind of tired of Hong Kong and want to relocate to Singapore to work as a tutor. The problem is, I am not Singaporean nor was I educated in Singapore. All I have is work experience in HK, graduating from a top university in HK.
What are the real chances of me obtaining an employment pass or visa for one of the academic centers in Singapore?
The answer to the question in the title ("How can I get a visa to teach in Singapore") is — as noted by @Traveller in Comments — by satisfying the eligibility criteria.
The answer to the question in the last paragraph ("What are the real chances of getting a visa or employment pass?") is unknowable. No one here knows your complete history nor the information you might submit in a visa application; no one here is Singapore Immigration.
We also don't know whether you'd be successful in finding employment if you entered Singapore as a tourist. (See, for example, the answer to this earlier question.)
Remember that SE sites (like this one) seek declarative answers, not opinions. The many variables and unknowables in your situation make this question unanswerable.
