I am starting IT studies. As someone always interested in computers I have paths in my head how to get needed information. There is also a luxury of testing anything learn in practice by for ex. contributing to open source or creating a server.
Math was always interesting for me too, but I haven't spend time on learning it much, I have many lacks from middle school and there are topics I know about but can't use them in practice or have no intuition or forgot how to formally write them.
So I started to try to learn, as a self-learner most time I spend on Wikipedia and forums, but those turned out to be death end when it comes to understanding whole topic and not just reminding one thing.
So question to you that are learning math: how do you do so? And I also never learned anything in a typical "school" way, I always need to feel interest or have a goal in something.
Either go with working through textbooks on your own, as has been stated by others, but that approach requires tons of discipline as the subject matter can get quite dry and frustrating at times. Or, I'd say ideally, enroll in courses at a local community college. The one I went to had four calculus classes, linear algebra and differential equations, along with statistics and I believe some kind of math programming course (my have just been part of other classes). So you cab get into fairly advanced stuff going that route.
If you want to learn even more after that, you'll have a solid basis to continue self study. Hell, you might even have a good start towards a bachelor's in math.