The general answer to any 'How do I become a researcher in X?' is typically to get a PhD in X. It also comes with perks like being immersed in a lab with similarly minded people, access to resources, classes, mentoring and not lastly, job opportunities.<p>That being said, if all you care about is learning so that you can build on your own, and you can pay for the computing resources yourself (don't underestimate that part!), it should be totally possible to go your own way, provided you have a decent background in math.<p>I'd start with some of the basics like the Hastie et al. ESL and the Goodfellow DL books, if you haven't already worked through them, and then look at the papers at the latest conferences. Read them, look up the papers they cite and the papers that cite them, basically build up your Google-Scholar-Fu.<p>Depending on how motivated you are, I reckon it should be possible to learn how to build something cool (not necessarily academically publishable) quite a bit faster than the typical 4-6 years to get a PhD. But don't forget that in DL a lot of the edge comes from having access to gigantic data sets and the infrastructure to train 1bn+ parameter models on massive GPU clusters.