Quoted By:
I'm probably not the best person to offer advice, but start with drawing from life... photos and whatnot.
Even if you are only going to draw anime/cartoon/whatever, you need to know how things naturally look. By just drawing shapes with no context starting off, you aren't going to know how they go together properly. It will also give you an idea of how things like clothes, hair, and whatnot normally act.
You can draw it however you like (so long as you aren't hurting anyone), but you can't draw a teapot without knowing what one actually looks like. Although, really, I should take my own advice.
Contributing a sketch to make my comment irrelevant.