Hey man, salute to you for wanting to start a career in the music industry.

I'm a freelance acoustic guitarist since 2010 and I can tell you that, like any other industry, it is not THAT easy to be in.

BUT it is still possible to earn a living in Singapore as a musician although I'm not sure of your targeted income per month in order to live comfortably or consider this as a full-time job. I would say that it's quite a good life. Doing what you love and getting paid at the same time.

Here are some things that I would suggest you to do.

1) Knowledge of Music
Don't ever stop learning. Keep on practicing and creating whenever time permits you. Create loads and loads of tracks, compositions, arrangements etc on your free time.

2) Portfolio
Create a Channel and upload ALL of your stuff there. Why? Here you can compile all of your works and let your potential clients check you out before they decide to hire you. Honestly, this works for me. I house all my videos on my performances on with a playlist and send clients whenever necessary.

Also, create a "Showreel" with works that you've done in the past for your clients to see when you meet them (if applicable).

3) Network
After creating your portfolio, you need to network with people. There are a ton of video agencies who are looking for jingles, compositions for film or commercial etc etc. Approach them with your portfolio and (if you're starting out), try to take however much money as they give you. Take it like an "Intern" project and put it with your portfolio.

Another way to create all these networks is by approaching Film students who are desperate for tracks. I've done this before and some of the film students eventually graduated and do their own films. Who knows? With good relationships, they might call you one day!

LASTLY

I think pursuing music and a psych degree at the same time is good as long as you know how to juggle and prioritize your time. What is your end goal? Is a psych degree the "fall back" if you don't "Succeed" in doing music full time?

I wish you all the best man!

Cheers!
Cheng