>The real niche that needs to be filled here is not more textbooks, it is a really really good description of how to actually teach yourself this stuff on your own.
I don't think you can. Sure there are a select few insanely motivated geniuses who could do it. But learning math is just really, really hard. Harder than anything most people ever come in contact with. It's kind of like being able to punch yourself in the face. You can try to, but you'll never be able to do it with the same force as someone else. Or like being on a sports team, where a good coach will push you far beyond the limits of what you could have possibly set for yourself. This is coming from someone who taught themselves to code completely solo from nothing and built a successful career as a software engineer. I've recently gone back to school because I simply could not teach myself even remedial high school math with sufficient rigor to prepare for upper division science/engineering courses.
I don't think you can. Sure there are a select few insanely motivated geniuses who could do it. But learning math is just really, really hard. Harder than anything most people ever come in contact with. It's kind of like being able to punch yourself in the face. You can try to, but you'll never be able to do it with the same force as someone else. Or like being on a sports team, where a good coach will push you far beyond the limits of what you could have possibly set for yourself. This is coming from someone who taught themselves to code completely solo from nothing and built a successful career as a software engineer. I've recently gone back to school because I simply could not teach myself even remedial high school math with sufficient rigor to prepare for upper division science/engineering courses.