How do I diversify my portfolio?

You can buy various countries ETFS and that will achieve diversification for that purpose.

I used to have a mental block that i should only buy Sg stocks as i could scuttle butt here.

But in recent years i realised the quality of SGX companies are just not there. The market is simply not big enough for them to grow and once they hit a certain size, the founders of good companies start to slow down.

I personally prefer the US and HK market is much bigger and it'd be a better place to start with.

Some resources for individual stocks:

https://www.hkexnews.hk/index.htm

https://sg.morningstar.com/ap/main/default.aspx​​​

I dont personally diversify based on exchanges. I prefer diversifying based on the best comapanies regardless of which exchange they are on.

If you handpick out quality companies, invest in them at the right price and always keep some portion of cash to invest more during dips. Never buy everything in the first tranche, split into 2 or 3 entries to average down cost price

Definitely explore more countries exchanges. US and HK exchanges have a lot of companies that could grow bigger and faster as their home market is already bigger than Singapore, and a lot of them even venture out of home market and grew even bigger as well.

I personally think diversify in term of sector and nature of the business.

Depends on your personal risk profile. A very general guideline that I read from Hardwarezone when I started investing is to use 110 - your age = % in stocks. For example, if you are 30:

110 - 30 = 80% in stocks, 20% in bonds. As to the breakdown inside, you can also put a mixture of growth investing, value investing and dividend investing. So the idea is not to diversify in all industries and countries, it would just be asset classes where all your assets are the best of the best in whatever they do.