[LionessLover]

a) get started on something - if you can't decide, roll the dice and pick something at random

b) ignore everything else until you are done

c) repeat

Don't worry that at your pace it will take ages - very soon you will develop an idea how to rank what you should look at next. If you don't, go back to a).

Obviously it's useless to think about it too much when your knowledge about a subject consists mostly of holes and gaps, so first gather data (a).

I can't quite see how concrete your question is, but try Khan Academy. Follow the suggested order if you have no preferences.

[demonshalo]

pretty much this.

The last math class I took was in high school and I dropped out of college because my CS degree required me to do a metric fuckton of math, which I hated at the time.

A few years ago I got interested and started working on Integer Factorization. It is not that likely that I will solve that problem but in the past few years I have learned a lot more math by attempting to solve that problem that I learned in college!

Moral of the story: Just have fun and try to solve some problem(s).

[kinai]

But some areas require knowledge base of others

[LionessLover]

Which you won't find out unless you start - somewhere, anywhere. How are you going to find out when you just sit there and think about something you know nothing about? Wait for sudden enlightenment? Math is one off the easiest subjects to get started, soooooo many starter books and by now even great online courses (again: Khan Academy, for the basics, probably many more). So much guidance. There is so much out there - free and easily accessible thanks to the Internet, the problem isn't "how do I get started" but "what resource do I use to get started".