Thank you all for your inputs. It's very interesting to see so many different ways to kick start a fresh new project.
With my recent time spent on making a new game, I realised things I do that are outside of my expectations: at the very beginning I started off with programming the core game mechanics (where all the maths are calculated, etc), thinking that's a fairly natural priority to tackle on. Then, also very naturally, I'd get tired of piecing all the pure logic together and start procrastinating. When I return to the project few days later, I restarted the project from the GUI. Now to my own surprise, the game already looks 50% complete to my plan and I can see myself finishing the game in 4 days.
Programming is my capability, but I've always enjoyed design more than maths.
Hope this thread reaches out to people who want to make a game but feel inconfident in anyway.