I’m in a very similar boat. I didn’t find math interesting in any capacity until I read Frege’s foundations of mathematics when I was about 21 or so. Unfortunat

I’m in a very similar boat. I didn’t find math interesting in any capacity until I read Frege’s foundations of mathematics when I was about 21 or so. Unfortunately, at that point my skills had degraded so much that I could barely get through basic geometric and algebraic problems. Since then, I’ve managed to greatly improve my understanding through self-directed learning to the point that I’m able to use mathematical concepts to make sense of other domains. My approach is a bit less structured than what others have recommended. I typically start by gathering tons of materials on the domain, say, digital signal processing. I then read things carefully, accepting that I won’t understand everything right away. Whenever I encounter something I don’t understand that seems important, I’ll sit down with a pen and paper or open vim and quite literally go point by point and try to write an explanation of the concept and make sense of it for myself. This method has served me pretty well for learning about new things. I think one thing you cannot get around, which others have also mentioned, is that the process is necessarily slow. trying to come up with detailed explanations for yourself takes time, as does rereading material, practicing, and learning to apply what you’ve learned. I think the biggest mistake autodidacts can make is rushing through things. It can be hard to resist the temptation to go fast sometimes, but it’s really important to dwell on things and go slowly