Amass a fan base, extend your reach outside Singapore and globally - if you can translate your text, post in Chinese/Japanese and Korean websites. Target the USA too with Tumblr, Twitter and Instagram. If possible try to participate in overseas conventions. (I have an American friend who sells Pokémon and Korra fan art in US conventions and easily makes 3k each time, but she took years to amass a fan base on Tumblr. Of course it'll be expensive for you since you have to keep flight tickets in mind so you have to make sure you can recoup your losses before you go.) another Singaporean I know goes to CTN in LA.

To get a fan base you will probably have to draw things people like first; cats, anime fanart, Pokémon, overwatch.....Yuri on ice....see what the trend is and fanart. Got to get them to like your art/work before you can get them to like and then pay for whatever you draw. Everything you do here is to amass a following so that when you release personal work you will already have an audience.

Understand that for many many years you will have to do all kinds of unrelated things to earn money. My friend would make Pokémon keychains out of shrinkies and sell them online. That used to be her side income in college. The guy who made stardew valley worked at movie theaters for income while making the game.

Be damn good at drawing.

And don't give up!