Well, I'd suggest avoiding the Mike Rice school of coaching.
Realistically though, I think the best play would be to volunteer as a counselor at a camp somewhere so you can see the work up close. Getting a HS JV or freshman gig isn't that hard, really. Especially at a private school, because they're usually desperate to find someone competent enough to show up, especially at non-competitive institutions or schools like where I once coached where all of the kids had to be involved in a sport for a certain number of trimesters of their academic career.
But the coaching camp experience would give you a coaching reference to be able to land some kind of lower level HS job where you can use the tactics you learned at camp (drills, etc.) to implement if you can manage to land some kind of freshman basketball assistant job or at a small school, a stipend to be head coach.
But yeah, it's not really realistic to think you're going to show up off the street and make a living at something that has so many people trying to get in, unless you have an in.
Hell, outside of the camp to some sort of HS freshman/JV thing which I think is your best bet for references/experience, you'd almost be better off working in the classroom as a faculty member at an private school or community college and then trying to latch on as an unpaid assistant to the basketball program. Even if you're just watching at first and even if the coach isn't very good, with the right place you can almost land yourself into a "volunteer assistant job" but then you've "coached college" and use that experience down the road to land a head coach job at the freshman or JV high school level once your experience is up to snuff or you've found a program that's not competitive where you can learn along with them.