Apply for junior developer positions at companies that interest you. If you can code, in this market you can get a job. With a strong mathematical background you will likely be snapped up. Seriously, apply to some junior developer jobs. I think you'll be pleasantly surprised at how easy it is to get a job if you can actually write code.

If you're not confident enough that you can write code well yet, then practice. Build side projects. Contribute to open source. Although a CS degree is informative, useful and enjoyable, it's absolutely not required currently.